Broke a rear wheel, so I...,...,... - Pocket Bike Forum - Mini Bikes
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Broke a rear wheel, so I...,...,...

What's happening, y'all? I know I've been MIA for a short while (since the TNT135). Like I said, I'll be around though. I have acquired what I believe is a new-old stock 49cc 2 stroke pocket bike from eBay. I was seriously only on there looking for a rear wheel (here comes the story).
So I was out at the school playground/parkinglot (my own little, personal neighborhood pocket bike track!) riding the 1st pocket bike I bought (junk 4 stroke from MPR). I was there for quite a while & decided it's time to call it a day, I was getting tired. Anyway, riding back home my leg started cramping up, as usual I just kind of straightened it out but this time it made it worse instead of helping. So my [email protected] tried to slightly stand up on the footpegs (lol)...,...,...bad idea! The front started violently shaking & I couldn't set back down fast enough to let it straighten itself out. So of course this little bike comes out from under me. Wasn't that big of a deal really, but it is slightly embarrassing to crash a pocket bike going in a straight line (LOFL)! I went to ride it the next day & the tire is flat. I put air in but hear it coming back out somewhere, long story short, wheel cracked where the spoke meets the "tub".
I ran across a dude on eBay with like 8 or 10 49cc, 2 stroke bikes for like $250 & free shipping. I messaged him to make sure it was actually a 2 stroke bike & not just the picture of one. It showed up & its most definitely a brand new 2 stroke pocket bike. The plus side is I've got a new rear wheel to mount my PMT back up to (LOL).
I'll get some pictures tomorrow when I take it out to the garage & get the fairings off to check everything over. I've got to pick up a velocity stack & an air filter (already have a 15mm carb on the bench), I may be able to score one from a guy I know, I just have to call him & possibly go out and pick it up.
Anyway, if one of you dudes are wanting an extra 2 stroke pocket bike there's definitely some floating around on eBay. Just thought I'd say so.
I'll update with pictures soon

Randall
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post #2 of 40 (permalink) Old 1 Week Ago
Re: Broke a rear wheel, so I...,...,...

Most pocket bikes have tubeless tires, so if the rim is cracked its probably leaking there.

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Yes, the wheel was damaged when I crashed it last time. That particular pocketbike came with tube/tires installed. I put new valve stems & PMTs on it.
The spoke has a hairline crack where it meets the “tub” of the wheel.
I think it could be run with a tube installed, but I’m not going to do that, it’s a safety issue for sure. No one wants to be riding something when a rear wheel lets go, especially when I knew it was like that.
Now I need to find a wheel that’s not $70+ to replace it with. That’s almost half the cost of the bike by the time it’s shipped & a new tire installed. Same reason I was like “well....I’ll just buy this entire bike”
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Re: Broke a rear wheel, so I...,...,...

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Originally Posted by MiniPilot View Post
Yes, the wheel was damaged when I crashed it last time. That particular pocketbike came with tube/tires installed. I put new valve stems & PMTs on it.
The spoke has a hairline crack where it meets the “tub” of the wheel.
I think it could be run with a tube installed, but I’m not going to do that, it’s a safety issue for sure. No one wants to be riding something when a rear wheel lets go, especially when I knew it was like that.
Now I need to find a wheel that’s not $70+ to replace it with. That’s almost half the cost of the bike by the time it’s shipped & a new tire installed. Same reason I was like “well....I’ll just buy this entire bike”
That's why we used to just chuck them in the shed and buy another....If you tried building a cag from the frame up it would cost ya 2-3x the cost of buying another whole bike....

Im surprised you didn't crack or bend the cheap rim edges just by changing the tires..The aluminum is ultra soft yet brittle...…..

When I used to build bicycles with alky powered chainsaw engines the rear spokes could only handle so much pressure before they tore out and the rim collapsed under power....It definitely was a wild ride when it happened....There weren't too many bikes with heavy duty rims/tires to utilize back then either....LOL

There was a member who bought one of those 2 stroker GP-RSR's from ebay...Im pretty sure I mentioned it in your MPR thread....He received a 2 stroker with reduction transmission and it went a topspeed of 20mph just like the 4 stroker......….It just has better/easier ways to make it faster.....

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Yes, the wheel was damaged when I crashed it last time. That particular pocketbike came with tube/tires installed. I put new valve stems & PMTs on it.
The spoke has a hairline crack where it meets the “tub” of the wheel.
I think it could be run with a tube installed, but I’m not going to do that, it’s a safety issue for sure. No one wants to be riding something when a rear wheel lets go, especially when I knew it was like that.
Now I need to find a wheel that’s not $70+ to replace it with. That’s almost half the cost of the bike by the time it’s shipped & a new tire installed. Same reason I was like “well....I’ll just buy this entire bike”
That's why we used to just chuck them in the shed and buy another....If you tried building a cag from the frame up it would cost ya 2-3x the cost of buying another whole bike....

Im surprised you didn't crack or bend the cheap rim edges just by changing the tires..The aluminum is ultra soft yet brittle...…..

When I used to build bicycles with alky powered chainsaw engines the rear spokes could only handle so much pressure before they tore out and the rim collapsed under power....It definitely was a wild ride when it happened....There weren't too many bikes with heavy duty rims/tires to utilize back then either....LOL

There was a member who bought one of those 2 stroker GP-RSR's from ebay...Im pretty sure I mentioned it in your MPR thread....He received a 2 stroker with reduction transmission and it went a topspeed of 20mph just like the 4 stroker......….It just has better/easier ways to make it faster.....

Good Luck
This doesn’t have any transmission on it, clutch bell housing & pinion drive in front. That’s why I believe this thing is new-old stock. Looks kind of like a MTA2, but you guys would know better than I, as I’m a pocketbike noob.
I sat those PMTs in the box they shipped in and set them in front of the register with our heat on in the house so they were warm & pliable before mounting. Didn’t take them to the garage until it was time to mount to the wheels. Made mounting them a breeze with a set of spoons.
I haven’t touched it yet, did some errands with the wife & some Christmas shopping, so I just got back to the house. I’m still going to post up pictures for confirmation of if this is what I believe to be new-old stock.

Randall
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Re: Broke a rear wheel, so I...,...,...

You might check out, www. scooterparts4less .com, he had some pretty good deals before on whole rims with tire mounted with China slicks. He has reg., soft, and ultra soft tires too which I have on my 50cc C1.

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Re: Broke a rear wheel, so I...,...,...

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You might check out, www. scooterparts4less .com, he had some pretty good deals before on whole rims with tire mounted with China slicks. He has reg., soft, and ultra soft tires too which I have on my 50cc C1.
Scooterparts4less is pretty much out of business...……...I went on their site not too long ago and when you click on the pics to order the pages either say "forbidden domain" or "404 not found"..…

Best way would be to put a wanted ad on craigslist....When I do I get pics of very tempting things to buy aswell....LOL.

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Got the PMTs swapped over to the new bike today. Took it apart (somewhat) to make sure things were all good (chain got an oil bath, had to straighten forks in the triples, greased axles, swapped front wheel, changed rear tire to PMT, drilled a few holes in stock air box & got rid of some extra plastic from casting) As promised, pictures coming.
The bike is most definitely not “new-old stock”. There’s a nameplate on the side that has a build date of 2019.
I fired the bike up, started easily & it’s pretty loud (lol). I let it run in the driveway for about 10 minutes after adjusting idle a little.
It’’s supposed to be dry & around 40-45 the rest of the week, so guess what this guy is doing.?!?.!?.! 🤙🏻🏁🏍️
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Re: Broke a rear wheel, so I...,...,...

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Got the PMTs swapped over to the new bike today. Took it apart (somewhat) to make sure things were all good (chain got an oil bath, had to straighten forks in the triples, greased axles, swapped front wheel, changed rear tire to PMT, drilled a few holes in stock air box & got rid of some extra plastic from casting) As promised, pictures coming.
The bike is most definitely not “new-old stock”. There’s a nameplate on the side that has a build date of 2019.
I fired the bike up, started easily & it’s pretty loud (lol). I let it run in the driveway for about 10 minutes after adjusting idle a little.
It’’s supposed to be dry & around 40-45 the rest of the week, so guess what this guy is doing.?!?.!?.! 🤙🏻🏁🏍️
Very nice looking bike....As for the actual year of manufacture I don't think its a 2019 model......Nameplates can be made then riveted on....Theres many truckbox loads of bikes sitting at California loading docks that could still be bought and sold aslong as its not sold in a state that outlaws the sale of 2 stroke modeled engines...

The GP-RSR's w/2 stroke engines and reduction transmissions they sell on ebay are 2012 models....Judging by the tubing,paintjob,plastic gastank instead of steel and light scale rust on the TF-8mm chain tells me its a 2009/2010 model replated as 2019..They also rivet the floatbowl on too after 2010 instead of using screws......…...

After 2010 they put spark arrestors inside them that kill power......You can tell if you have a spark arrestor by feeling with a long thin rod through the exhaust pipe exit...Steel gastanks started in 2011 too...…..



If it is a 2009 model with no EPA restrictors youll see speeds of 27-28mph after proper break-in...

Youll love the powerband a lot better than the 4 stroke joke hands down and youll be wanting more uumph out of it especially from a dead standstill and out of the corners.....

For that you have the WYK pumper race carb setup , rocket key,hp flywheel mod and clutch mod w/hp clutchsprings...............

Have fun....

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Originally Posted by CAM2 View Post
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Originally Posted by MiniPilot View Post
Got the PMTs swapped over to the new bike today. Took it apart (somewhat) to make sure things were all good (chain got an oil bath, had to straighten forks in the triples, greased axles, swapped front wheel, changed rear tire to PMT, drilled a few holes in stock air box & got rid of some extra plastic from casting) As promised, pictures coming.
The bike is most definitely not “new-old stock”. There’s a nameplate on the side that has a build date of 2019.
I fired the bike up, started easily & it’s pretty loud (lol). I let it run in the driveway for about 10 minutes after adjusting idle a little.
It’’s supposed to be dry & around 40-45 the rest of the week, so guess what this guy is doing.?!?.!?.! 🤙🏻🏁🏍️
Very nice looking bike....As for the actual year of manufacture I don't think its a 2019 model......Nameplates can be made then riveted on....Theres many truckbox loads of bikes sitting at California loading docks that could still be bought and sold aslong as its not sold in a state that outlaws the sale of 2 stroke modeled engines...

The GP-RSR's w/2 stroke engines and reduction transmissions they sell on ebay are 2012 models....Judging by the tubing,paintjob,plastic gastank instead of steel and light scale rust on the TF-8mm chain tells me its a 2009/2010 model replated as 2019..

After 2010 they put spark arrestors inside them that kill power......You can tell if you have a spark arrestor by feeling with a long thin rod through the exhaust pipe exit...Steel gastanks started in 2011 too...…..



Youll love the powerband a lot better than the 4 stroker hands down and youll be wanting more uumph out of it especially from a dead standstill and out of the corners.....Have fun....
You bring up some very valid points. Right on!
Can you tell by the photos if that’s a reed engine? Just curious because I have a brand new adjustable carburetor sitting on the bench I’d like to install soon. If it has reeds in there I’d prefer to go ahead and order carbon fiber reeds & install them while I’m already in there...,...,...2 birds, one stone thing.
I’m seriously not going to go mod crazy with it, I do appreciate an adjustable carburetor, velocity stack & filter though. So that’s definitely happening.
For now I’m going to go ride it and see how she does.
Thanks Cam2
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You have the Reed inducted CAG the one that we all know and love...

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Re: Broke a rear wheel, so I...,...,...

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You bring up some very valid points. Right on!
Can you tell by the photos if that’s a reed engine? Just curious because I have a brand new adjustable carburetor sitting on the bench I’d like to install soon. If it has reeds in there I’d prefer to go ahead and order carbon fiber reeds & install them while I’m already in there...,...,...2 birds, one stone thing.
I’m seriously not going to go mod crazy with it, I do appreciate an adjustable carburetor, velocity stack & filter though. So that’s definitely happening.
For now I’m going to go ride it and see how she does.
Thanks Cam2

Yes its definitely reed inducted...The engine is a 44mm brushcutter engine.It looks like the split transfer port cylinder too......

Theres a reed plate mod and reedstopper mod you can do to it....






If you disassemble the whole engine,blueprint the whole thing,add a 3rd port,pumper carb and better exhaust along with other mods and youll have a powerhouse that can pull from a dead stop ,pump out some nice midrange power aswell as deliver a lil extra revs and take that tool engine out of its element and more motorbike oriented...

Heres a link to the carb...………….

https://www.amazon.com/TC-Motor-Raci...%2C172&sr=8-29

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You have the Reed inducted CAG the one that we all know and love...
Thank you, MrKitty. Definitely good to know. So I will be ordering some carbon fiber reeds to replace the stockers while I’m in there changing the carburetor out.
Much appreciated, thanks again.
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You bring up some very valid points. Right on!
Can you tell by the photos if that’s a reed engine? Just curious because I have a brand new adjustable carburetor sitting on the bench I’d like to install soon. If it has reeds in there I’d prefer to go ahead and order carbon fiber reeds & install them while I’m already in there...,...,...2 birds, one stone thing.
I’m seriously not going to go mod crazy with it, I do appreciate an adjustable carburetor, velocity stack & filter though. So that’s definitely happening.
For now I’m going to go ride it and see how she does.
Thanks Cam2

Yes its definitely reed inducted...The engine is a 44mm brushcutter engine.It looks like the split transfer port cylinder too......

Theres a reed plate mod and reedstopper mod you can do to it....






If you disassemble the whole engine,blueprint the whole thing,add a 3rd port,pumper carb and better exhaust along with other mods and youll have a powerhouse that can pull from a dead stop ,pump out some nice midrange power aswell as deliver a lil extra revs and take that tool engine out of its element and more motorbike oriented...
NOICE!!!
Thank you, Cam2. I appreciate it.
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Re: Broke a rear wheel, so I...,...,...

What you have is an MT-A2 full fairing Cagillari Daytona. When you look for parts search, MT-A2 pocket bike parts.

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NOICE!!!
Thank you, Cam2. I appreciate it.
Just never lose track of the fact that the engines they put on all low level Chinese made pocketbikes are industrial tool engines...

Theyre 1.6hp for 40mm and 1.9hp for 44mm engines...

Never buy into the putting a full circle crank in a tool based engine is gonna work because it reduces internal volume yada,yada,yada,yada…..The design of the tool based reed inducted crankcase doesn't allow the golden rule of building a performance 2 stroker to be utilized...........

Simply put into question;-Would you deliver performance breathing through a straw in your throat or a garden hose?

Even those ADA 4 petal reedblock setups don't work especially with an engine equipped with a FCC...Its like threading a needle with a sausage.

As a brushcutter or auger engine built with 3:1 reduction transmission to raise the engines torque factor theyre more than adequate in torque and power for performing their job with a lifespan of 120hrs of continuous duty service life..

When they become loaded with an adult rider above 75-80lbs and linked to a pinion gear with no reduction they can become a bit taxed and continuous duty cycle cut in virtually half....

Taxing builds up heat.....Heat taxes parts and causes blow-by especially if a 2 stroker is pushed past its limits...Its a viscious cycle that works in favor of the Chinese because you will need another bike or engine or even a topend /hop-up kit...

Not properly breaking-in the engine by waiting the time to go full throttle plus following the rules by doing the most proper break-in you can do will scorch the cheap-azz rings and after the rings get scorched they get rubbery and they don't seal as they should which in turn bleeds back a lot of spent gasses back into the jug area instead of out of the exhaust........The scorched rings also scores-up the cylinder...….

This engine was run under a half hour and obviously broken-in very-very wrong...… In chinese 2 stroke patience is a virtue....LOL

When it gets to this point its time for either another engine or a full total rebuild as metal and debris has made it everywhere in all the bearings....



When you blueprint a 2 stroke engine you're essentially smoothing out all sharp edges to reduce turbulence..Turbulence is bad for building performance in a 2 stroke engine.What you're also doing in the blueprinting process is defining the pathway you want the fuel to take which also increases velocity...





Velocity is whats needed to maintain proper flow of the atomized mix at all power levels to deliver the power potential locked with-in...

85% of a stock tool based engine can be modified easily with a Dremel,jewelers fileset,regular fileset and sandpaper plus polish wheel....

Changing out the cheap Chinese crankcase bearings and seals with better higher quality made components will also help by reducing vibes that reduces revs aswell as keeps the crankcase positively sealed with lower drag crankcase seals...........For crankcase bearings I like to use Timken brand 6202-C3 deep groove design and for the seals SKF #5808...

Squish is usually set in the safe zone so it delivers around 8:1 compression with a squishband of around .061-.062"...Removing the basegasket and simply yamabonding,hondabonding or motosealing the cylinder down to the crankcase will increase compression to almost 10:1 and bring the squishband to around .049"....Real performance starts under .045" but its a lot better than the .061-.062" they're built with...…..

When you increase performance and power youre giving the engine the ability to afford its passenger and their demands instead of becoming the whipping boy...……..

Its a lot better to increase the roof height of the transferports the thickness of the gasket lost but the decreased height can and will increase fill velocity too so its a tradeoff that's virtually 50/50 and cancels each other out pretty much unless you grind-in a 3rd 4th or 5th extra ports to the cylinder then there are rules...…

Polishing the transferports and jug enhances snappiness of throttle response aswell……..

Im sure you know from racing about GP racebikes…...They're not secretly built in some secret underground lair...…...They're bone stock off the showroom floor models taken fully apart and the engine is fully balanced and blueprinted then reassembled and tuned to with-in a millimeter of its life in all aspects also lightened where it could be with lots of carbon fiber.....…..

Theres no special billet crankshafts,cylinders etc other than what the factory puts into them...…..

Best thing to do is go on amazon and buy another bone stock engine for $80.00 ,take it apart,mod it up right and swap it in-place of the bone stock engine,,heat cycle it and break it in right and you'll be very-very amazed at the difference...……

Night and Day just doesn't cover it...….Maybe winter and summer or 19th and 20th century….LOL

This is what your engine looks like before the Chinese remove the cooling sleeve around the cylinder , remove the gastank attached atop aswell as the box muffler affixed below and slap it into a frame with wheels with either a clutch housing with 6-7tth pinion or a 3:1 reduction transmission...…..
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Re: Broke a rear wheel, so I...,...,...

Quote:
Originally Posted by CAM2 View Post
Just never lose track of the fact that the engines they put on all low level Chinese made pocketbikes are industrial tool engines...

Theyre 1.6hp for 40mm and 1.9hp for 44mm engines...

Never buy into the putting a full circle crank in a tool based engine is gonna work because it reduces internal volume yada,yada,yada,yada…..The design of the tool based reed inducted crankcase doesn't allow the golden rule of building a performance 2 stroker to be utilized...........

Simply put into question;-Would you deliver performance breathing through a straw in your throat or a garden hose?

Even those ADA 4 petal reedblock setups don't work especially with an engine equipped with a FCC...Its like threading a needle with a sausage.

As a brushcutter or auger engine built with 3:1 reduction transmission to raise the engines torque factor theyre more than adequate in torque and power for performing their job with a lifespan of 120hrs of continuous duty service life..

When they become loaded with an adult rider above 75-80lbs and linked to a pinion gear with no reduction they can become a bit taxed and continuous duty cycle cut in virtually half....

Taxing builds up heat.....Heat taxes parts and causes blow-by especially if a 2 stroker is pushed past its limits...Its a viscious cycle that works in favor of the Chinese because you will need another bike or engine or even a topend /hop-up kit...

Not properly breaking-in the engine by waiting the time to go full throttle plus following the rules by doing the most proper break-in you can do will scorch the cheap-azz rings and after the rings get scorched they get rubbery and they don't seal as they should which in turn bleeds back a lot of spent gasses back into the jug area instead of out of the exhaust........The scorched rings also scores-up the cylinder...….

This engine was run under a half hour and obviously broken-in very-very wrong...… In chinese 2 stroke patience is a virtue....LOL

When it gets to this point its time for either another engine or a full total rebuild as metal and debris has made it everywhere in all the bearings....



When you blueprint a 2 stroke engine you're essentially smoothing out all sharp edges to reduce turbulence..Turbulence is bad for building performance in a 2 stroke engine.What you're also doing in the blueprinting process is defining the pathway you want the fuel to take which also increases velocity...





Velocity is whats needed to maintain proper flow of the atomized mix at all power levels to deliver the power potential locked with-in...

85% of a stock tool based engine can be modified easily with a Dremel,jewelers fileset,regular fileset and sandpaper plus polish wheel....

Changing out the cheap Chinese crankcase bearings and seals with better higher quality made components will also help by reducing vibes that reduces revs aswell as keeps the crankcase positively sealed with lower drag crankcase seals...........For crankcase bearings I like to use Timken brand 6202-C3 deep groove design and for the seals SKF #5808...

Squish is usually set in the safe zone so it delivers around 8:1 compression with a squishband of around .061-.062"...Removing the basegasket and simply yamabonding,hondabonding or motosealing the cylinder down to the crankcase will increase compression to almost 10:1 and bring the squishband to around .049"....Real performance starts under .045" but its a lot better than the .061-.062" they're built with...…..

When you increase performance and power youre giving the engine the ability to afford its passenger and their demands instead of becoming the whipping boy...……..

Its a lot better to increase the roof height of the transferports the thickness of the gasket lost but the decreased height can and will increase fill velocity too so its a tradeoff that's virtually 50/50 and cancels each other out pretty much unless you grind-in a 3rd 4th or 5th extra ports to the cylinder then there are rules...…

Polishing the transferports and jug enhances snappiness of throttle response aswell……..

Im sure you know from racing about GP racebikes…...They're not secretly built in some secret underground lair...…...They're bone stock off the showroom floor models taken fully apart and the engine is fully balanced and blueprinted then reassembled and tuned to with-in a millimeter of its life in all aspects also lightened where it could be with lots of carbon fiber.....…..

Theres no special billet crankshafts,cylinders etc other than what the factory puts into them...…..

Best thing to do is go on amazon and buy another bone stock engine for $80.00 ,take it apart,mod it up right and swap it in-place of the bone stock engine,,heat cycle it and break it in right and you'll be very-very amazed at the difference...……

Night and Day just doesn't cover it...….Maybe winter and summer or 19th and 20th century….LOL

This is what your engine looks like before the Chinese remove the cooling sleeve around the cylinder , remove the gastank attached atop aswell as the box muffler affixed below and slap it into a frame with wheels with either a clutch housing with 6-7tth pinion or a 3:1 reduction transmission...…..
Hey Cam2,
Thanks for a very informative, detailed post & also the bearing part numbers, etc. I appreciate it all.
So, I got off work a little early & thought I was going to go put around on this thing to begin actual break in...,...,...not just let it run in the driveway for a few minutes.
Now, keep in mind this thing fired right up when I put gas in it (25:1 mix) the other day...,...,...I go out and it starts really hard, but it started. let it warm up for a minute or so, then go to ride it. it starts moving then seems like it floods out. It kind of bogs and then dies. So me and this thing have a half hour "why won't you run like the other day" war in the driveway, only for me to come out losing.
It would start up and idle, so I left it sit there for a minute & it stayed running then all of a sudden dies (idled for about 1:00-1:30). Since it was starting and idling, i kept trying to take it down the street thinking, maybe it just needs to run & clear some crap out of itself.It would start to go, bog & die. Randall's wrong again (lol). So I'm going to go ahead and chalk this up as I need a new carburetor (have one, just not the manifold with pulse port), fuel lines, fuel filter (have that too) & also a new exhaust. Cause you have to know that the exhaust didn't stay in tact. The muffler separated from the bracket that holds in in the very back.
Just a little bad luck is all, I'll get it sorted out. I was a little bummed out at first, but now I actually find it pretty funny. I break 1st bikes wheel, look for a wheel buy new bike & it's broken & I've not even rode it. LOFL at my luck sometimes.
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Re: Broke a rear wheel, so I...,...,...

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Originally Posted by MiniPilot View Post
Hey Cam2,
Thanks for a very informative, detailed post & also the bearing part numbers, etc. I appreciate it all.
So, I got off work a little early & thought I was going to go put around on this thing to begin actual break in...,...,...not just let it run in the driveway for a few minutes.
Now, keep in mind this thing fired right up when I put gas in it (25:1 mix) the other day...,...,...I go out and it starts really hard, but it started. let it warm up for a minute or so, then go to ride it. it starts moving then seems like it floods out. It kind of bogs and then dies. So me and this thing have a half hour "why won't you run like the other day" war in the driveway, only for me to come out losing.
It would start up and idle, so I left it sit there for a minute & it stayed running then all of a sudden dies (idled for about 1:00-1:30). Since it was starting and idling, i kept trying to take it down the street thinking, maybe it just needs to run & clear some crap out of itself.It would start to go, bog & die. Randall's wrong again (lol). So I'm going to go ahead and chalk this up as I need a new carburetor (have one, just not the manifold with pulse port), fuel lines, fuel filter (have that too) & also a new exhaust. Cause you have to know that the exhaust didn't stay in tact. The muffler separated from the bracket that holds in in the very back.
Just a little bad luck is all, I'll get it sorted out. I was a little bummed out at first, but now I actually find it pretty funny. I break 1st bikes wheel, look for a wheel buy new bike & it's broken & I've not even rode it. LOFL at my luck sometimes.
Typical Chinese crapbox….Just know if honda sold a similar model it would be like 3grand as it would be refined and built a lot better..

What your bike is exhibiting is typical...The Chinese rubber they use inside the petcock aswell as for the fuellines are very ethanol fuel sensitive they swell up aswell as shrink up too.....It sounds like you may of forgotten to turn the petcock off too..

Golden rule is to replace the fuellines to 1/4" ,upgrade fuel filter to 1/4" nylon mesh high flow get a STENS brand 1/4" in-line fuel shutoff and also do the petcock mod right off the bat although I suggest just going with the pumper carb kit and calling it a day as temps are in the 40's there and the bike is jetted for around 70-75* so having a mainjet assortment pack is essential..

With a pumper carb its a lot easier simply richening the LSN with a screwdriver...As you can see from the brushcutter pic the fuelline is very very short between the tank and the carb..

What you need to do is loosen the screws on the headpipe for the muffler,,remove the fuel from the floatbowl with the bottom evac screw,remove the sparkplug,dry it off,pull pullrope with fuel petcock turned off about 10x,put plug back in turn n fuel ,set choke and pull pullrope…

After it starts the build-up of fuel in the headpipe will start to blow out,,tighten screws and rev it a lil to expel the rest of the fuel build-up..

If you don't crack the seal youll keep scavenging back the fuel from the j-bend and flooding the sparkplug..

For break-in you should of started out with 32:1 for 2 tankfuls up to 1/2 throttle then 40:1 for 2 tankfuls up to 3/4 throttle….Then you have the option of staying safe or going for a lil more performance with 50:1 aswell as have the ability to ride it like you stole it.....……..25:1 is just way too much oil.....

One thing I'd definitely do is get rid of the cheap Chinese Torck brand sparkplug for NGK BM6A / BM7A
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Quote:
Originally Posted by CAM2 View Post
Quote:
Originally Posted by MiniPilot View Post
Hey Cam2,
Thanks for a very informative, detailed post & also the bearing part numbers, etc. I appreciate it all.
So, I got off work a little early & thought I was going to go put around on this thing to begin actual break in...,...,...not just let it run in the driveway for a few minutes.
Now, keep in mind this thing fired right up when I put gas in it (25:1 mix) the other day...,...,...I go out and it starts really hard, but it started. let it warm up for a minute or so, then go to ride it. it starts moving then seems like it floods out. It kind of bogs and then dies. So me and this thing have a half hour "why won't you run like the other day" war in the driveway, only for me to come out losing.
It would start up and idle, so I left it sit there for a minute & it stayed running then all of a sudden dies (idled for about 1:00-1:30). Since it was starting and idling, i kept trying to take it down the street thinking, maybe it just needs to run & clear some crap out of itself.It would start to go, bog & die. Randall's wrong again (lol). So I'm going to go ahead and chalk this up as I need a new carburetor (have one, just not the manifold with pulse port), fuel lines, fuel filter (have that too) & also a new exhaust. Cause you have to know that the exhaust didn't stay in tact. The muffler separated from the bracket that holds in in the very back.
Just a little bad luck is all, I'll get it sorted out. I was a little bummed out at first, but now I actually find it pretty funny. I break 1st bikes wheel, look for a wheel buy new bike & it's broken & I've not even rode it. LOFL at my luck sometimes.
Typical Chinese crapbox….Just know if honda sold a similar model it would be like 3grand as it would be refined and built a lot better..

What your bike is exhibiting is typical...The Chinese rubber they use inside the petcock aswell as for the fuellines are very ethanol fuel sensitive they swell up aswell as shrink up too.....It sounds like you may of forgotten to turn the petcock off too..

Golden rule is to replace the fuellines to 1/4" ,upgrade fuel filter to 1/4" nylon mesh high flow get a STENS brand 1/4" in-line fuel shutoff and also do the petcock mod right off the bat although I suggest just going with the pumper carb kit and calling it a day as temps are in the 40's there and the bike is jetted for around 70-75* so having a mainjet assortment pack is essential..

With a pumper carb its a lot easier simply richening the LSN with a screwdriver...As you can see from the brushcutter pic the fuelline is very very short between the tank and the carb..

What you need to do is loosen the screws on the headpipe for the muffler,,remove the fuel from the floatbowl with the bottom evac screw,remove the sparkplug,dry it off,pull pullrope with fuel petcock turned off about 10x,put plug back in turn n fuel ,set choke and pull pullrope…

After it starts the build-up of fuel in the headpipe will start to blow out,,tighten screws and rev it a lil to expel the rest of the fuel build-up..

If you don't crack the seal youll keep scavenging back the fuel from the j-bend and flooding the sparkplug..

For break-in you should of started out with 32:1 for 2 tankfuls up to 1/2 throttle then 40:1 for 2 tankfuls up to 3/4 throttle….Then you have the option of staying safe or going for a lil more performance with 50:1 aswell as have the ability to ride it like you stole it.....……..25:1 is just way too much oil.....

One thing I'd definitely do is get rid of the cheap Chinese Torck brand sparkplug for NGK BM6A / BM7A
Lol! I follow you, for sure. I mixed up some 25:1 cause the little manual that came with it said to run that for break in. I thought it was a lot of oil too...,...,...freaking 6oz per gallon! I was like “why don’t I just dump this oil in there and then add a splash of gas (that’s a joke, of course). I also actually remembered to turn that petcock to “off” after I ran it the other day.
I’m definitely just going to grab a pumper carb setup (manifold, gaskets, carburetor, v-stack & filter). I’ll just let the other one sit on the bench & go with a Walbro style H/L needle carb for the ease of adjustment as you stated.
The pipe has 2 holes in it, one before the “belly” the other where it used to attach at the very rear. So I’m going to get something else to rectify that one too.
Once again, I appreciate the help & advice, thank you sir.

Last edited by MiniPilot; 1 Week Ago at 07:08 PM.
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Re: Broke a rear wheel, so I...,...,...

Quote:
Originally Posted by MiniPilot View Post
Lol! I follow you, for sure. I mixed up some 25:1 cause the little manual that came with it said to run that for break in. I thought it was a lot of oil too...,...,...freaking 6oz per gallon! I was like “why don’t I just dump this oil in there and then add a splash of gas (that’s a joke, of course). I also actually remembered to turn that petcock to “off” after I ran it the other day.
I’m definitely just going to grab a pumper carb setup (manifold, gaskets, carburetor, v-stack & filter). I’ll just let the other one sit on the bench & go with a Walbro style H/L needle carb for the ease of adjustment as you stated.
The pipe has 2 holes in it, one before the “belly” the other where it used to attach at the very rear. So I’m going to get something else to rectify that one too.
Once again, I appreciate the help & advice, thank you sir.
Theres not too many choices for pipes....For what you have a JetPro would be good but if you start upping the HP the JetPro will start holding the engine back without mods..

Best thing to do is buy a cheap harbor freight migwelder……Putting a bigger 1"od mandrel bent J-bend with slip stream divergence cone in the inlet plus 4-6" extension added to the belly and stinger deleted or severely shortened will add plenty of performance....

Using donor pipes like 1.75" nickel/chrome pipes from a Harley and melding it with the stock pipe plus a new expansion chamber and a new larger inside diameter j-bend can net a fantastic looking aswell as performing pipe..



On tool engines tuned pipes don't work aswell even if theyre built for the porting..I built a tuned pipe for my Extreme XG499 stand up scooter and the stock box muffler gutted gave it a lot more lowend power aswell as better higher revs...…..

On tool engines the faster you can inhale air with the most velocity possible,blend with it with as much fuel as possible,cram it into the cylinder with lots of force and the spent gasses exits into the atmosphere with as little holdback as possible is what you want with what you have...Any holdback in the exhaust will just bottle up the atomized mix in the crankcase trapped in the cranks vortex..

This is a bone stock 40mm engine thoroughly modded..It has a WT603 pumper carb setup and stock modded exhaust....

As you can hear the exhaust tone aswell as pressure being exerted from the stinger the exhaust is holding the engine back..The pipe has been cut and modified with a rev pipe..Even if I put a JetPro exhaust it would be having the same issue..

click on pic to see vid.

trophy cag modded exhaust 1 by Dizzy Gillespie, on Flickr


https://www.flickr.com/photos/139167.../shares/7u8661

This is after just removing the stinger.....

trophy cag modded exhaust 2 by Dizzy Gillespie, on Flickr

Heres a bone stock cag for comparison.....Theres a huge difference between bone stock and stock modified when its done right...

bone stock cag by Dizzy Gillespie, on Flickr

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