Have A 2 Stroke A/C Pocketbike & Want To Make It Faster?????....Look Here If You Do..
So you have a cheap 2 stroker bike thats in need of some more power........Theres no real mystery to it and its quite general for most pocketbike engines like cags and x1's where both have different types of two stroker engines...
This Thread outlines JUST the D.I.Y mods aswell as Basic mods you can do to enhance power ......This thread does not cover porting or blueprinting.....Theres threads that outline the blueprinting and porting process and requires an attention to detail aswell as a dremel set fully loaded with assorted cutters/grinders...
...............................If you have an engine like this one.......................
...................................Here are the mods........................................
Change the Fuellines and In-Tank Fuel Clunker..........If the fuel in the tank is old ....remove the tank and wash it out with hot water ans dish soap then dry it out thoroughly........
Get rid of stock airfilter and get a velocity stack w/ built-in choke and a hp airfilter.....Now youre gonna ask where....??? Check out the PBP vendor supplier section for more info.....Usual cost for a setup is around $20 bux shipped.....I like to use ebay.........
There is also a DIY mod utilizing a laundry detergent bottle cap and some pantyhose...You use the palm of your hand as the choke... or if your handy can add a choke flap by removing the one from the stock airbox and rigging it to work........Cost of this Mod...maybe $2 bucks and 30 mins time.........
Just know that when you improve airflow intake youll be leaning out the engine severely so therefore some carb tuning may be required.......If you have a Walbro carb you have Lowspeed and Highspeed needles screws on the side of the carb that do almost the same thing the same way..
Heres a video for tuning the stock 15mm WYK carb.........
Walbro WT813 HP Pumper Carb Upgrade............. Using this carb will require you use an adapter plate or you mod the stock intake with JB Weld...Cost of this upgrade varies from $32.99-$50 bux...
JUST AS A NOTE>>>>>>>>>>>>....................I suggest you using new gaskets between the insulator block and engine aswell as between the carb too....Never trust old gaskets in this area and NEVER use RTV sealants!.. If youre handy you can buy a rolled sheet or rubber fibre material thats .025" thick to make new gaskets with.........
Lighten the flywheel by clipping the fins 3/8" shorter to reduce fin drag and reduce reciprocating weight....cost of this mod....30 mins of your time with a hacksaw ,,sandpaper and a file
Unmodded Flywheel......
Modded Flywheel..............
Add a rocket key.....Alot ask does it work and is it worth the effort and the money....The answer is YES....cost of this mod is under $10 bux..Daves Discount Motors is the best place to get them...You want the LARGE rocket key.............
Modify the Clutch.......This is done by crossdrilling the pads ,,adding a hp clutchspring,,deglazing the clutchpads and clutchbell with 100 grit sandpaper and deoxidize/de-rust clutch mount bolt shoulders and mount holes on the pads..When you reinstall the clutchpads make sure you use loctite on the screws.........cost of this mod.......30 mins labor with a handdrill,,some sandpaper,,metal polish and of course threadlocker.....
Get a quality brand sparkplug........NGK BPMR7A plug gap is between .030" to .035"
JUST AS A NOTE>>>>>>................ After you reinstall the coil after modding the flywheel/adding a rocket key and modding the clutches it will have to begapped properly......This is done using a business card that a true .020" thick........most use index card shreds but it has to be atleast .020" thick to maximum .024" thick....
DIY Boostbottle Setup............ Alot ask if boost bottles work and worth the effort......?.....The answer is YES....Theres many-many threads on what boost bottles do and how to make them..Do a search for past threads on the subject....I personally use them and get great results from the ones Ive built myself..
Get a Performance Exhaust...Theres JetPro pipes,,rev pipes and fatty pipes for these kind of engines,,The JetPro and Fatty pipes offer the best performance gains.........cost of this mod varies by model of bike and is between ...$39-$80..sometimes ebay has the ebst deals on exhausts..
Change the Gearing...... To gain more topend speeds you can either get a front sprocket thats 1-2 teeth larger or a rear sprocket between 6 and 10 teeth smaller...Seeings its easier to change the front sprocket Id go with that..
JUST An ENDNOTE>>>>>>>>>>.... Speeds and performance given will vary but will definately give you a noticeable improvement over being bone stock if done right..............If more power is desired I suggest you break out your dremel and learn how to use it well...
Re: Have A 2 Stroke A/C Pocketbike & Want To Make It Faster?????....Look Here If You
If you are looking to mod an engine like the first picture in this post.................Of course if you have a 43cc youll want 49cc but this is just to show the basic mods to giving the reeded engine a lil more kick in all powerbands....Theres many-many threads about BigBore Kits and what happens if you dont blueprint and rework alot of stuff to get them to work as intended...........
Heres what a basically modded reed inducted cag engine looks like.........
Remove Fueltank and Fuellines aswell as Fuelfilter.........Throw old lines and fuelfilter away..Wash out fueltank with hot soapy water and dry out thoroughly.....Upgrade the fuellines and fuelfilter to 1/4"...cost of upgrade.....$6-$8bux...
Do The Petcock Mod............Do a search for this mod.....The basics of this mod is to gut the petcock,,fill the cavity with JB Weld then when the JB cures drill straight through the fuel inlet through the bottom to eliminate that problem.......If you do the mod youll have to buy an in-line 1/4" fuel shutoff valve and install it in-line..........cost of mod.....$8-$10 bux
Velocity stack and hp airfilter................These items are designed to improve airflow therefore rejetting or adjustment of the c-clip on the needle will be needed to be done afterwards...........If jetkit is needed you can get one between $8 bux and $15 bux
Disassemble Carb and Clean it Out Thoroughly.....................Make sure the needle tip and seat lip are free of foreign trash and the float height is of optimal height......1/8" shy of the bowl seal lip is considered optimal float level height,,,,,
Replace Tin Reeds to Composite or Fiberglass........ Better reeds will enhance flow and offer alot of lowend power...cost of upgrade is between $6 and $20 bux
Perform the Reedstopper Mod..............This mod can be done with a grinding wheel and some sandpaper...alls you want to do is mod the reedstopper so the reeds open up a lil bit farther but not so far they hit the flywheel......cost of this mod....20 mins time....
JUST AS A NOTE>>>>>>>>>>>>>>>>>>>>..................When you do the reedstopper/reedpetal mod replace the gaskets....DONT REUSE THEM and DONT USE RTV!!!!...You can make new gaskets if your handy by buying a roll of .025": rolled rubber fiber gasket material and with an exacto blade and hole puncher make new gaskets to save time.............cost of roll...$4 bux at your local autoparts store..
Aluminum Pullstarter Mod......................An aluminum pullstarter offers alot of pulling resilience better that the stock plastic one.....It also helps absorb engine heat aswell...........cost of this upgrade is between $19 and $25 bux shipped
HP Sparkwire Mod......................Most coils the sparkwire just unscrews from the coil and one from an automotive set substituted to enhance spark delivery to the sparkplug to give more power and keep the plug cleaner and the throttle crispy...cost of mod....abe $5-8 bux for a eplaceent wre eeif you have an extra laying around....
NGK Sparkplug Upgrade....................................NGK sparkplug BMR6A is the best,,,BM6A is the normal sparkplug......Plug should be gapped between .030" - .035"...........cost of sparkplug is between $1 - $9......
If your no good at rejetting and fiddling around with floater carbs I suggest a Walbro WT series retrofit hp pumper carb kit as you see in initial picture..............cost of upgrade is between $49 and $60 bux depending where you buy from....I suggest this mod 100% because the ease of tuning is so nice.........You will need to mod the fuellines a bit but theres threads on how by a member named Jaloos...
Modding,,Lightening of Clutchpads.............................Crossdrilling the pads to lighten them and adding hp clutchsprings will raise the rpms the clutch grabs at to enhance bottomend takeoff aswell as midrange punch coming off a corner.........
JUST A NOTE>>>>>>>>>>>>>>>>>............................When you reassemble the clutches make sure you deglaze the pad faces and clutchbell with 100 grit sandpaper...Alot ask what clutch is better to buy.....Buy a stock type 3 shoe that has aluminum shoes and simply mod them..........Keep the stock clutchsprings somewhere safe.....Check our vendor supplier section for good places to buy.......I use ebay......
Lighten the Flywheel..............This can be done as a 12 fin,,9 fin or even a finger ripping 6 fin design.......cost of mod ...20-40 mins labor time with a dremel...This is my 12 fin design,...I mainly use 12 fin designs.
Adding A Rocket Key....................................Alot ask if this key actually works and worth doing...?.....The answer is YES!!!..The 10 degree advance it gives the ignition timing enhances power alot in every powerband....cost of upgrade is under $10 bux.....Theres a thread on how to install it here......... http://www.pocketbikeplanet.com/showthread.php?t=79475
Exhaust System Upgrade................You can port the exhaust port hole in the exhaust flange and mod the stock exhaust by adding 4-6" to the center section of the expansion chamber using a 2" Id piece of muffler pipe.......The extra length mekes a big difference and does it low budget...I have personally done it and it definately has worked great...............cost of upgrade varies on whether or not the mod can or cant be done by you..... heres a thread on the subject............. http://www.pocketbikeplanet.com/showthread.php?t=5722&highlight=stock+pipe+mod
There are upgrade exhausts like IP2,,,JetPro,,,Chrome hp style and 1 or 2 others......cost of upgrade is between .....$40 bux to $110.00...check the vendor supplier section of PBP aswell as the parts for sale section.......I use ebay...
Gearing Upgrades...........................To get better topend speeds you can go 1-2 teeth bigger on the pinion and as low as 13 teeth smaller than the stock rear gear depending how powerful the engine is upgraded to................Its easier to get a new clutch bellhousing complete with bigger pinion and swap it put......cost of upgrade is $20-$25 bux...
I Also Suggest if you buy a clutch bell housing complete that you buy a Clutch housing with 3rd bearing support.....................
After basic upgrades our bike will feel like it has more than double its current power......................Theres ways to get even further powerwise with a dremel set with bit assortment
Re: Have A 2 Stroke A/C Pocketbike & Want To Make It Faster?????....Look Here If You
Very good write up CAM!! They should sticky this.
For those who are wondering about these mods. I have a 2010 43cc HF Cag and have done these mods except for the flywheel because I've been riding. But I plan to do it this winter.
All I can say is this... What are you waiting for?? lol If your not too handy with a Dremel or scared to do all that grinding I highly reccommend these simple and easy mods.
It woke my 43cc right up! I could only imagine these mods on a 47cc engine. Doing these mods will also help you become more mechaniclly familiar with your bike. Which will be a building block if you choose to move onto porting and piston windowing etc.
All I can say is Trust CAM on these mods he's a guru.........
Re: Have A 2 Stroke A/C Pocketbike & Want To Make It Faster?????....Look Here If You
The blata does not come with a fuel filter.. Just be careful what goes in the tank..
None of my Euro Bikes came with filters..
Oh and you dont need to do any of these mods except maybe some Gearing changes.. lol... These are mostly for China 2 Strokes... All you might need to do is BluePrint the bottom end.. Thats in another thread and falls under the "Theres ways to get even further powerwise with a dremel set with bit assortment" catagory... Maybe a bigger carb...
Re: Have A 2 Stroke A/C Pocketbike & Want To Make It Faster?????....Look Here If You
If I am not sure, I pour the gas thru a V shaped coffee filter, or nylons can work to, some here has made there own V-stacks and put nylons over the front with a rubber band for a filter.
Re: Have A 2 Stroke A/C Pocketbike & Want To Make It Faster?????....Look Here If You
I just block the end off and pull..The suction pulls a good amount of fuel inwards to prime the engine enough to start...........
My newest lesser horsepower build-up.......It doesnt feel too less though when I put it on a couple heat cycles a few hours ago......Its got some pretty nice displacement.......LOL
This thing revs like its got a 4 barrel carb with an extra booster barrel.......LOL
Re: Have A 2 Stroke A/C Pocketbike & Want To Make It Faster?????....Look Here If You
Dude, if you need tools H/F Tools has a dremel kit w/ case I have one, it kicks but for $17.99 and a Metric tap & die set for $12.99 or something like that. Online only special for a few days. Maybe you can sign up and get that price. I have alot of air and electric power tools, got a 2.5hp 21gal tank, 150lbs compressor for $149.00 there. If you can afford, I highly recommend those two and a $10 set of small files, you will be in biker heaven. I keep them 3 buy me at all times, when working on my bikes, use them everyday.
Re: Have A 2 Stroke A/C Pocketbike & Want To Make It Faster?????....Look Here If You
got a question not sure how or where to post it so Im just going to dive in... I picked up an x7 r5 replica and the break levers are tired and dead so I was thinking of using so high end mtb break levers but here is the snag...the safety sensor in the rear break to start via electric starter. What do I do about that little guy? I was thinking of putting it in some sort of vallet box and strapping it out of the way somwhere behind my fairing. Any thoughts? hook a brother up
Oh its dual carb but there is no build thread...I had a dual carb with dual ADA 4 petal reedblock engine built too but it was a lil off in its port calculations where blowdown was being affected enough to cause irrepairable problems..........
The newest engines are dual carb but half reeded and half piston ported and were designed for GoPed racekarts.....Alls Im gonna say is try and build that type of engine at your own risk;-get to know a good machine shop and have lots of expendable cash on hand as parts dont just slip and bolt together letalone jive without some customizations..........
I have quite a few different twin carbbed engines of different types..A 137cc IAME racing kart engine...A few McCulloch Chainsaw engines and now a couple twin carb chinese engines.......I also have a dual sparkplug hemi-head engine too......Those are my secret weapon engines for now but someday may give the forum a peek......MUAHaHaHa..
got a question not sure how or where to post it so Im just going to dive in... I picked up an x7 r5 replica and the break levers are tired and dead so I was thinking of using so high end mtb break levers but here is the snag...the safety sensor in the rear break to start via electric starter. What do I do about that little guy? I was thinking of putting it in some sort of vallet box and strapping it out of the way somwhere behind my fairing. Any thoughts? hook a brother up
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