DIY pocket bike mods? Cheap mods?

[razor-]

Hey
i have a 47cc pocket bike completally stock exept for an advanced key timer.

Is there any mods that i can do for free to give better performance?

And YES i have drilled the intake cover.

Also what would be the best bang for my bucks considering i have a key timer?

Thanks

[SAM272]

cheap upgrades are things like the stiffer clutch springs, they will give you better off the line performance ...

decent reed valve will also be a cheap option

[Crash Dummy]

Take a look at the info posted on here in the past about advance timing keys. Removing that and putting in the stock one might be a good free performance mod. If not performance then longevity. It just depends whether your engine needs it or not.

[razor-]

but i just bought a performance key timer why would putting in the stock one be better than the performance one?

its pretty good off the line its more the top speed that i want to work on..

What would help my top speed? putting in a bigger FRONT sprocket or putting in a bigger REAR? Ive heard differenty from different places but i thought a bigger front sprocket would increase top speed?

[SAMMY]

bigger rear sprocket would help

[barnsey]

just search it on the fourms much easier and people wil not flame up over it

[Crash Dummy]

timing check

This is the thread I was referring to.
It isn't so much about performance as longevity. If your ignition timing is advanced too far your potentially going to do more harm then good mostly through pre-detonation where you get fuel partially igniting during the compression stroke where fuel in the combustion chamber can ignite on it's own then followed by the spark plug and vice versa, the effect is that these two flame fronts will crash into each other and it creates what is known as detonation. This is also referred to as pinging and less often as pinking. (dunno where that term came from) The kind of shock placed upon the engine internals can be likened to striking the piston crown with a hammer at whatever rate the engine is spinning at the time.

Doesn't sound real pretty does it.
Anyway I'm not trying to scare you off it, Just check out RD Racing's instructions and make sure it's safe.

[serbius4]

check out the stickys in this part of the forum, heaps of good ideas, UPDATED; want your cag engine quicker?
ive done most of the mods suggested on this one and my bike hammers now, even with a stock exhaust, theres one on modding a stock carby i did this one and put it on my stock bike, it got heaps more power and speed with only the carb, pretty much all ya need is basic tools and a dremmel, hope this helps

[nascar815]

if you go a bigger front sprocket only go one more tooth a bigger rear sprocket will hurt your top end and i would try lightening the flywheel. take off every other fin. I tried the advance key and replaced it back with the stock. didnt like the way it ran.

[razor-]

ok thanks
although ive heard snapping off the flywheel fins can be bad for it?

my bike vibrates A LOT could this be caused be un-even flywheel balance?

i dont know if my fywheel is balanced or not as i havent looked at it yet.
How will i know if the keytimer is doing my bike hurm?

Sorry if these questions sound supid im a novice 14yr old and only have a cheap e-bay bike

Thanks