Ebay 47 or 49cc motors? - Pocket Bike Forum - Mini Bikes
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post #1 of 45 (permalink) Old 06-13-2019 Thread Starter
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Ebay 47 or 49cc motors?

Hi, does anyone use any of the Ebay 47cc or 49cc motors? And if so how are they? And I did search the forums for awhile and didn't find this listing. So if its already been asked a bunch of times before sorry. I'm a new guy here and just try to figure some stuff out.

And a second question is what pumper carb are most of you using for the MTA2 bikes. Are you buying the $50+ name brand carb or one of the knock offs?

Thanks in advance.
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post #2 of 45 (permalink) Old 06-13-2019
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Re: Ebay 47 or 49cc motors?

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Originally Posted by 2004YZFR1 View Post
Hi, does anyone use any of the Ebay 47cc or 49cc motors? And if so how are they? And I did search the forums for awhile and didn't find this listing. So if its already been asked a bunch of times before sorry. I'm a new guy here and just try to figure some stuff out.

And a second question is what pumper carb are most of you using for the MTA2 bikes. Are you buying the $50+ name brand carb or one of the knock offs?

Thanks in advance.
Amazon , ebay it doesnt really matter. The engines are manufactured in china shipped in a huge box with minimal packing between each...

The difference in 40cc,43cc,47cc and 49cc is the mystery.....Some claim that the 40cc and 47cc are made up numbers to get the 44mm bore bikes into the country faster by qouting the engine power as being 2cc less...Some say its to give merit to those bigbore kits and Big Bore kits with FCC crank that was supposed to boost an engine to 52cc's......lol

Others say that the engine had a 32mm stroke back in the earlier years and now the engines are bumped up to a 34mm stroke to make them 49cc which makes zero sense to me because then there would be different cylinders sold for 32mm and 34mm stroke engines yet there isnt....

For aslong as I can remember theres no difference in strokes from 2003 and now and whats funny is you have one of the older 2004 engines that would definitely hold that fabled 32mm stroke crank inside the crankcase of the original engine.....

To me its just an identifier between reeded and piston ported engines.....



Theres no way to tell if youre getting a 40mm bore with 10mm pin or a 44mm bore with 10 or 12mm pin reedported engine without measuring the piston,pin and the cylinder too.Although there are some identifiers that differentiate the two if youre good at attention to detail and knowing what to look for.......

Heres a 40mm 10mm pin crank versus a 44mm 12mm pin hd ctank..In the background amongst the many pistons across the workbench in my hobbyroom on the upper righthand part of the pic is the 10mm journal and rod of the 43cc/49cc piston ported engine...….




Some Chinese made 2 stroke tool engines are a lil better than others but its very hard to know whos got the best but back in the day I used to hunt down The TM casted and SanRen built engines / TM and SanRen casted cylinders are the better ones IMO as the chrome on those cylinders are the toughest and they were casted with a lil extra power too.

The best and easiest carb to tune that offers the best benefits is buying the WYK192 15mm pumper carb setup for $20-25 bux...…

This is the pumper carb setup........Youll also need a fuelline kit from Home Depot

https://www.ebay.com/itm/Racing-Carb...QAAOSw0w1ct9y6

For the engine I'd buy this one because the transmission is an extra bonus that you can resell for $25-30 bux to recoup back money....Best part is it comes with an aluminum pullstarter with aluminum claw too

https://www.ebay.com/itm/49CC-2-STRO...nd!11207!US!-1

cheap hp engine......

https://www.ebay.com/itm/52-49cc-Big...IAAOSwMhVcDi-I

Heres what the engine looks like when its utilized as a tool based engine...……




Good Luck
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post #3 of 45 (permalink) Old 06-15-2019 Thread Starter
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Re: Ebay 47 or 49cc motors?

CAM2, your awesome, thanks again for all of the great information. If I get one of the pumper carbs that you showed me do I need to get a different throttle cable assembly? Or will the stock one work?

And you said that I should replace my crank seals since the motor is 15 years old and had been sitting for so long. Is there a easy way for me to check them to see if they are bad before I pull this little motor apart?

I fired the bike up yesterday with the choke on and let it run for a minute or so then turned the choke off and just let it idle for a few minutes. Then i just blipped the throttle and let it run for a bit and it seemed fine. I think my oil to gas ratio is still to high.

It was smoking a lot and took out those mosquitos. I'm going to drain the tank and go get some fresh super today and use a ratio jug to measure the oil to gas more accurately this time. I'm using Yamaha semi synthetic oil now. Is there any problem with using this or is a non synthetic oil better?
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post #4 of 45 (permalink) Old 06-15-2019
Re: Ebay 47 or 49cc motors?

Your throttle cable should work fine, changed my piston carbs to pumper carbs on Cags, never had a problem, yet, lol.
A China WT-603 pumper is about $35, a real Walbro is about $50. Intake manifold $18, V-stack $9, swivel $2, and throttle cable arm to hold cable $10 and then an air filter. The best place is Dave's Discount Motors, in Utah. davesmotors.com, they carry scooter and gas RC cars, parts, carbs and engines. Got an Walbro HDA48B 16mm carb for $30 on sell, best for the Cag cause it does not have a return line only an gas inlet. Similar to these photos.
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post #5 of 45 (permalink) Old 06-15-2019
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Re: Ebay 47 or 49cc motors?

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Originally Posted by 2004YZFR1 View Post
CAM2, your awesome, thanks again for all of the great information. If I get one of the pumper carbs that you showed me do I need to get a different throttle cable assembly? Or will the stock one work?

And you said that I should replace my crank seals since the motor is 15 years old and had been sitting for so long. Is there a easy way for me to check them to see if they are bad before I pull this little motor apart?

I fired the bike up yesterday with the choke on and let it run for a minute or so then turned the choke off and just let it idle for a few minutes. Then i just blipped the throttle and let it run for a bit and it seemed fine. I think my oil to gas ratio is still to high.

It was smoking a lot and took out those mosquitos. I'm going to drain the tank and go get some fresh super today and use a ratio jug to measure the oil to gas more accurately this time. I'm using Yamaha semi synthetic oil now. Is there any problem with using this or is a non synthetic oil better?
Just like EPR stated the throttle cable will work just fine...Just make sure you get a pusher spring.....

The pusher spring makes the throttle snap back really quick......



You do realize as 2 stroke mix sits the oil and gas seperate in the tank or gas can its sitting in and all the oil goes to the bottom being the heaviest between the two...It even seperates in the floatbowl and the fuellines…...LOL

That's another reason why I love pumper carbs ….You can shake the tank up then circulate the separated fuel back to get mixed also to get the proper mix with-in seconds after starting up...

Im sure that you can fathom whats going into the carb when you open the fuel valve so Im very sure your ratio was a lil off until the vibes of the running 2 stroker re-mixed the two in the tank for you....

With 2 stroke bikes you have to shake them up a lil before opening the fuel valve and starting it up.........

Im also sure theres a pretty nice collection of gas n oil in the j-bend of the exhaust pipe that needs to be blasted out....

Bone stock cag vid...…..This is an older model....Listen to it wheeze and sputter until I clean it out by flogging the throttle with that floater carb…...Listen to the idle run higher then lower

bone stock cag by Dizzy Gillespie, on Flickr

Modified cag with race porting and pumper carb vid...stock 43cc engine...

trophy cag modded exhaust 1 by Dizzy Gillespie, on Flickr

Stinger removed to reduce backpressure...Notice how the bike just stays running pretty consistent.....?

That's the magic of the pumper carb also pretty good tuning..

trophy cag modded exhaust 2 by Dizzy Gillespie, on Flickr

Heres the same cag with dual chamber rev pipe and frame remodel.....It needed an exhaust tone adjustment as it was super obnoxiously loud also needed a lil seating comfort for getting the rider weight over the frontwheel a lot better to keep it planted...Unicycles are fun but not at 35mph 18" off the asphalt….LOL

trophy cag modded exhaust 3rp by Dizzy Gillespie, on Flickr

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post #6 of 45 (permalink) Old 06-15-2019 Thread Starter
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Re: Ebay 47 or 49cc motors?

I worked on my bike again today. I drained the fuel and went and got some fresh super and mixed the oil 50.1 for the first time. It took long time to get it started. I just put the chock on and didn't give it any throttle. After it finally started I ran it for a minute or so on the choke and then turned it off and let it idle for a minute. Then it did the rev up and die thing again. I tried to get it to run again. And after bunch of sweating and cussing I drained the fuel again and pulled off that new Amazon carb.

I pulled my old stock carb apart again and cleaned it and blew it all out again. I reinstalled it on my bike added fuel again. And after about 3 pulls it fired up. I ran it on the chock for a minute then let it idle for about 2 minute or so.

Then me and my son rode it for about 20 minutes. It lives again!! My new plug comes in on Monday so I will install that and see how it goes. Hopefully I can ride it for awhile and then put my body work back on and post a video on this old little bike.

Everyone has been super cool on this site and helpful!
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post #7 of 45 (permalink) Old 06-15-2019
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Re: Ebay 47 or 49cc motors?

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Originally Posted by 2004YZFR1 View Post
I worked on my bike again today. I drained the fuel and went and got some fresh super and mixed the oil 50.1 for the first time. It took long time to get it started. I just put the chock on and didn't give it any throttle. After it finally started I ran it for a minute or so on the choke and then turned it off and let it idle for a minute. Then it did the rev up and die thing again. I tried to get it to run again. And after bunch of sweating and cussing I drained the fuel again and pulled off that new Amazon carb.

I pulled my old stock carb apart again and cleaned it and blew it all out again. I reinstalled it on my bike added fuel again. And after about 3 pulls it fired up. I ran it on the chock for a minute then let it idle for about 2 minute or so.

Then me and my son rode it for about 20 minutes. It lives again!! My new plug comes in on Monday so I will install that and see how it goes. Hopefully I can ride it for awhile and then put my body work back on and post a video on this old little bike.

Everyone has been super cool on this site and helpful!
Awesome to hear you didnt give up and got it running...Thats a pretty clean looking bike.........

This engine had low runtime of about 25 minutes before it stalled and they couldn't get it started then chucked it in the shed and forgot about it until they sold the house and were cleaning out the shed but as you can see it kinda sat in the wrong spot for those 10 years he said it was in there..........

The old owner was surprised when I didnt care of it ran of not I just needed it as a whole to revive and modify........Had it been started it wouldve ran very crappy..



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post #8 of 45 (permalink) Old 06-16-2019
Re: Ebay 47 or 49cc motors?

Don't think that clutch would work very well either, lol. I have a bunch of new alum arm clutches that I was putting hp springs on, for some new hp engines I am building from parts. Some of them were hard to move, that's why CAM2 tells you to take them apart and make it work right. New parts don't always work right, sounds like the engine kept going lean which makes it rev high. If its hot you need a bigger main jet, stock is about .64, you probably need a .70mm jet to get enough gas. They have jet kits with a .66, .68, .70, .72, .75mm. The new carbs float level could be very low, which could run the float bowl dry. Or you could have had an air leak behind the carb, which would make run lean w/ high RPMs. On any carb, you have to remove the brass main jet, and the atomizer tube, and run a small wire thru w/ cleaner to get crap out that even air pressure won't remove. I would modified the new carb, many things you can do to make it better.

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post #9 of 45 (permalink) Old 06-16-2019
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Re: Ebay 47 or 49cc motors?

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Don't think that clutch would work very well either, lol. I have a bunch of new alum arm clutches that I was putting hp springs on, for some new hp engines I am building from parts. Some of them were hard to move, that's why CAM2 tells you to take them apart and make it work right. New parts don't always work right, sounds like the engine kept going lean which makes it rev high. If its hot you need a bigger main jet, stock is about .64, you probably need a .70mm jet to get enough gas. They have jet kits with a .66, .68, .70, .72, .75mm. The new carbs float level could be very low, which could run the float bowl dry. Or you could have had an air leak behind the carb, which would make run lean w/ high RPMs. On any carb, you have to remove the brass main jet, and the atomizer tube, and run a small wire thru w/ cleaner to get crap out that even air pressure won't remove. I would modified the new carb, many things you can do to make it better.
You're absolutely right about that one EPR...The clutcharms were very sticky from rust and oxidized aluminum...….The clutcharms would've engaged got stuck and the bike would've kept going or stalled..LOL

Funny part was the people selling the cag were only asking $30 bux for it too.....LOL

The older engines didn't have EPA strangleholds like restricted carbs and restricted exhausts also had a better casted carb with a slightly bigger mainjet so your theory about it being too lean seems to be spot on.....

You'll never get one of the older carbs brand new at this point seeings the carbs are so cheap to just replace when they give problems...

The rubber in the newer petcocks are a lot more reactive to ethanol now than they were in the older carbs too so they swell up and restrict fuel a lot lesser...….



I hope you don't think I magically cut the pipe in the right spot...I used a scope to find the restriction then gauged it with a rod...…..LOL

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the flywheel on the older ones was a lot better as well

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Re: Ebay 47 or 49cc motors?

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the flywheel on the older ones was a lot better as well
Yep...They used slightly better magnets in them.........

You have an old crank from a reed ported engine Im almost positively sure.....


There was a debate years back when i first joined about the stroke of a FCC to the stroke of a regular crank...

Get a small cardboard box or a flat piece of cardboard...Take one of your stock cranks and cut a 15mm hole for the crank arm to poke through....

Stretch the crankrod out to its furthest point and put a mark with a sharpie dead center of the rodhole..

Rotate the crank down 180 degrees to retract the rod and take the sharpie and make another mark dead center..

Pull crank up and measure the distance between the two marks..
Those of you all that have a crank laying around and want to give some input do the countrywide experiment and post up what you all get...

You should get a measurement of roughly 1.26" or 32mm's........

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post #12 of 45 (permalink) Old 06-16-2019 Thread Starter
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Re: Ebay 47 or 49cc motors?

I might try that EPR, since I have 2 now. I have no idea what size main jet came in the Amazon carb. It is super hot here now I think its suppose to be 103 today so i'm sure that leans it out a bit.

The main jet on the new carb is a different style then the stock carb. It is just 1 piece that screws out and the old carb has the main jet and the base. I didn't see a size or # on either one.

I got my new NGK plug in the mail yesterday after noon so i'll install that and give it a go.

How fast should these old MTA2 bikes go with a 200 + pound adult on them? I'm going to try one of the gps speedometer apps.
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Re: Ebay 47 or 49cc motors?

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I might try that EPR, since I have 2 now. I have no idea what size main jet came in the Amazon carb. It is super hot here now I think its suppose to be 103 today so i'm sure that leans it out a bit.

The main jet on the new carb is a different style then the stock carb. It is just 1 piece that screws out and the old carb has the main jet and the base. I didn't see a size or # on either one.

I got my new NGK plug in the mail yesterday after noon so i'll install that and give it a go.

How fast should these old MTA2 bikes go with a 200 + pound adult on them? I'm going to try one of the gps speedometer apps.

Hotter doesnt always mean its gonna run leaner especially if you live in a place with high humidity....Water vapor takes place of air.....

If you live in a place with low humidity you would be correct........

The best and absolute way to tell how your engine is liking the tune is to pull the sparkplug and read it...Its been a common practice since the start of the combustion engine...…

2 stroke engines require a special kind of give and take tune to get the most power out of them aswell as overall useage...

The way the condition of the sparkplug looks gives you an indication of which way to go with the tune of the engine as in 2 stroke what seems too lean could be too rich and fogging the plug at wide open throttle instead of the engine sucking more air less fuel...…


With fixed mainjet carbs its harder to get that perfect give and take balance so they run on basically a flatplane powerband......

Soon if you get deeper into this hobby and do alot more riding youre gonna realize why I choose the streetfighter look....With the amount of plug pulling and carb tuning I have to do the lower half and front part of the body would be sitting on the bench anyways seeings it takes atmost 10-15 minutes just to remove the fairing and same time to reinstall not adding the time to fix the problem......That's ridetime lost...….Youre also gonna learn if youre gonna ride a lot more too you need to start buying more sparkplugs than 1 at a time... I buy my 2 stroke engine sparkplugs 5-10 at a time and always get the bulk buy discount too...

An older Mt-A2 went between 26-30mph without mods with a rider weight between 180-200lbs...Like I stated in many threads and probably here too that top speed depended on who manufactured the engine as some engines were alot more powerful than some others...

When I did my Cag cag cag build thread here back in 2011 when I was searching for build materials I ran across an ad for a cag that said it went 40mph.....I was looking at the pics and said to myself theres no way even though it had 7/55 gearing too.....



I gave the kid my GPS and told him to take a blast on it.....He did,,I read the results and he went 39.7mph on a bone stock 40mm bore engine with 7/55 gearing..Only mod was a stinger delete..LOL

I was gonna buy it anyway and even though there was no debating his claims the overall condition of the bike was quite rough so he accepted half of what he was asking which was $20;-he was asking $40.....LOL


I also built a 2004 Ziemini Mt-A2 cag with a 5 port 2pc cylinder engine with a 7/49 gearing plus a modded stock exhaust with 6" belly extension and a 19mm Del rep carb that nobody else could ever get tuned on a cag until I achieved it...

I just put the engine together like an average joe would and with my 160lb brother on it and got 49.3 mph out of it but it didn't last very long..…..After a rebuild and refinements I got an extra 3.7mph out of it...….

3.7mph seems like a small number but if you compare the difference between 32 & 34mm stroke engines you're only discussing 1/16 of an inch also to mention if two cags raced and one was 3.7mph faster than the other after running wide open for an hour the faster cag would be over 3.5 miles further...…

That's quite a lengthy distance for such a puny variable...…...LOL


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Re: Ebay 47 or 49cc motors?

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Originally Posted by 2004YZFR1 View Post
I might try that EPR, since I have 2 now. I have no idea what size main jet came in the Amazon carb. It is super hot here now I think its suppose to be 103 today so i'm sure that leans it out a bit.

The main jet on the new carb is a different style then the stock carb. It is just 1 piece that screws out and the old carb has the main jet and the base. I didn't see a size or # on either one.

I got my new NGK plug in the mail yesterday after noon so i'll install that and give it a go.

How fast should these old MTA2 bikes go with a 200 + pound adult on them? I'm going to try one of the gps speedometer apps.
Oh and as far as seeing a size on the carb or the mainjet.........You wont,,,Thats where the savings comes in and the unsureity begins when you buy Chinese made stuff...…

Even if you buy the $20 jetpack mainjet assortment kit with only 5-6 different sized jets where 3 jets right off the bat will be unuseable without mods to the stock carb like opening it up to 15mm unless you buy the $30 drill kit but will be a waste of money buying the jetkit anyway seeings you already have 2 jets to start with that you can drill 1 step bigger at a time til you get the tune right.....

You'll also have to hold the jetpack jets up to the light to gauge the sizes by-eye then mark them with an etcher with Dots then use a ledger in the tuning log and hope you guessed right...……

I mod my jets sizes with a $6 mig welder tip cleaner tool from Home Depot..Its a Helen Keller technique that Ive come to learn to do quite well throughout my many years of experience with various types of carbs also tuning r/c nitro cars starting as a kid and still run them to this day.. .......……..



The modded carb on the left with rounded floatbowl is an older model carb......I used to mod all the stock carbs..run them on modded engines to get the results to log then I gave them away to forum members who just paid for shipping costs so they can utilize it or it would've just went in a box labeled crap......They were happy as hell with them.….LOL



Thats why if you plan on keeping that floater carb you should make a small tuning log then buy either the pilot/mainjet drillkit that doubles as sizing gauge pins too then you can make and mark your own custom jets and seasonally you can rejet then jot down the changes...…

Even doing something as simple as installing a velocity stack with HP airfilter it would require a mainjet change from 1 jetsize minimum up to 2 higher....


Also on them carbs theres a c-clip that controls needle height which adjusts fuel rate and get a lil more useage out of the installed jet a lil richer or leaner...Theres 5 notches on the needle and factory setting is middle notch.....

Theres also something called a rich/lean float setting where you can adjust the fuel level in the bowl to increase/decrease fuel delivery into the venturi....

That's why I love the $20 pumper carb...doing just a small adjustment with a jewelers screwdriver while running/revving it on a stand and theyre always running like a top in seconds with no tuning logs to keep..

The reason why youd keep one is so you don't forget how the carb was set last time you used it as time goes by or buying a $30 drillset seeings they have whats called a factory setting and if you get lost in your tune you just reset back to factory setting and start all over......LOL


With a floater carb its drain carb and tank,pull carb off then pop carb top or remove just the floatbowl off and remove floatbowl,change mainjet or tweek float setting while smelling raw fuel the whole time...It gets old quickly especially when you eventually crack the intake or wear out the carb gasket and start air leaks.......



If you could take a side profile pc of the engine cylinder similar to the way the black bike is positiond I can identify if your engine has the 40mm or 44mm piston which is another difference in jetting on those carbs too yet how can it be seen through a floatbowl or the differences known without part numbers by the seller...….LOL

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Re: Ebay 47 or 49cc motors?

For $10 you can buy a Stihl MS250 16mm pumper carb, clone WT-813 w/ accel pump and choke plate that can be removed and use a Dave's 19 x 44mm V-stack with choke arm for more air flow. Best part is there is only a gas inlet, no return, perfect for a reed port engine. It will bolt up to a piston or reed port engine manifold. The hardest part was making & installing a throttle arm and swivel for the throttle cable.
DDM has a V-stack with built in choke plate now, 1 piece $10, swivel $2, throttle arm $10, about $35.
ADA racing .com has closeout on pocket bike parts. Billet alum throttle arms for $3

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post #16 of 45 (permalink) Old 06-18-2019 Thread Starter
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Re: Ebay 47 or 49cc motors?

Hello gentlemen and ladies? I took pictures of my old carb to show you but my iPhone and my iMac aren't speaking to each other right now.

I put the new NGK plug in and got the bike started fairly easy. I ran it on the choke for a minute and then let it idle for about 2 minutes. and took it out foe a run.

It seemed to run good and it was pulling good. I got a short full throttle run and then backed off a bit. Then I went down the next street which is slightly down hill. And got a good full throttle pull.

I think that was the best run I've ever gotten on this bike. Then I just slowed down a bit and the motor just cut out. I checked to make sure I had gas in the tank and tried to start it a bunch of times but it didn't fire off.

It seemed like it wanted a few times but it didn't start again so I gave it a rest for tonight.

I think i'm going to replace the 15 year old coil like CAM 2 suggested.

What do you guys think?
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Re: Ebay 47 or 49cc motors?

Sure sounds like a coil going bad, it runs decent cold, then it gets hot and stops.

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Re: Ebay 47 or 49cc motors?

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Originally Posted by 2004YZFR1 View Post
Hello gentlemen and ladies? I took pictures of my old carb to show you but my iPhone and my iMac aren't speaking to each other right now.

I put the new NGK plug in and got the bike started fairly easy. I ran it on the choke for a minute and then let it idle for about 2 minutes. and took it out foe a run.

It seemed to run good and it was pulling good. I got a short full throttle run and then backed off a bit. Then I went down the next street which is slightly down hill. And got a good full throttle pull.

I think that was the best run I've ever gotten on this bike. Then I just slowed down a bit and the motor just cut out. I checked to make sure I had gas in the tank and tried to start it a bunch of times but it didn't fire off.

It seemed like it wanted a few times but it didn't start again so I gave it a rest for tonight.

I think i'm going to replace the 15 year old coil like CAM 2 suggested.

What do you guys think?
I also think you should buy the new crankseals and replace them...…Theyre $7 bux and cheap insurance against any airleaks occurring at the crank at wide open throttle....

All of this isn't unfounded and part of the end of building a 2 stroke engine is doing a process called "Doing a Leakdown / Pressure test" which is something the Chinese never do when they build their engines...


A leakdown test tells if all your sealing points are correctly sealed on a 2 stroke engine and able to handle the pressure exerted under engine operation without a failure.....….I call it proofreading your build...LOL



Pull the sparkplug and see what it says.....Ive had engines run on the cusp of being too lean and killed the sparkplugs from thermal overload or even fouled it from "Glazing".......

If the sparkplug tip is white or gray in color you lean fouled/killed the sparkplug....

You might want to switch to a cooler tip sparkplug too if it is lean fouled /glazed....If youre running a NGK BM6A run the Autolite equivalent of the NGK BM7A

If the sparkplug tip is black in color you have a jetting issue or a coil going/gone bad......


Like EPR stated about possible culprit to the problem and Ill also add its a great idea and practice to always change the coil and cheap insurance too also to mention that the coil should always be changed when doing a small engine tune-up where the engine is over 5 years old or you're doing a topend rebuild...........


Too bad you didn't have a short vid of how it was running...Musicians have an ear for the tone whereas my dad used to say I have an ear for the tune..Airleaks too...LOL

Good Luck

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Last edited by CAM2; 06-19-2019 at 06:13 PM.
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post #19 of 45 (permalink) Old 06-19-2019 Thread Starter
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Here is the new plug that I installed and got the 2 good pulls on and about 10 minutes running time on. I ordered the new coil but it won’t be in till the middle of next week.

Do you have a video or a write up on how to do the crankcase seals?
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Re: Ebay 47 or 49cc motors?

Quote:
Originally Posted by 2004YZFR1 View Post
Here is the new plug that I installed and got the 2 good pulls on and about 10 minutes running time on. I ordered the new coil but it won’t be in till the middle of next week.

Do you have a video or a write up on how to do the crankcase seals?
Theres no video I know of but alls Ill say is its not very hard at all....Alls needed to do the job the easiest way would be to purchase a cheap steering wheel puller set from the local autoparts store.

https://www.ebay.com/itm/New-11pc-Un...oAAOSw~kVbn~JS

The process is simple after you remove the clutch,flywheel and woodruff keys from the crank...


You just use a small screwdriver or sharpened pick to remove the seal from the crank then you lube the crank with a lil 2 stroke oil and push the seal on flush to the case with your fingers.....


Removing the flywheel affords the availability to also order a brand new aluminum clutch also a rocket key and do the flywheel mod...........



12fin flywheel mod...…...

Cut
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Last edited by CAM2; 06-19-2019 at 10:16 PM.
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