Engine modifications

[honda_atc200es]

well i tried asking on the forum more specifically related to this, thumpertalk.com, but they havent answered meyet, and i know that here a 3ww there are tons of helpful people which is why im still an active member without even owning a trike.

Anyways i now own a 107cc pitbike and since i got it i have always wondered about more speed and power, like i do with all my bikes, and heres what i have found thats in my price range.

12.5:1 high compression pistons, which should be a nice improvement over the stock 9:1's what kinda fuel do i have to run, and what kina improvement will i see, any downside?

highperformance cam, supposedly increases hp by 2, would be nice its only 70 bucks, what will i see from a mid- to high range cam, how hard is instalation and is it worth it

oil cooler, this bike is only air-cooled, and when i ride, i ride hard, seems like i need one, theres so many choices, $60 billet coolers, or 120 for radiator style, even 200 for high capacity, what should i get keeping in mind i plan on going with a 146cc bore kit in the future.

and finaly on my list (for the moment) is a gearing change towards the top speed end, this bike has a crapload of torque and acceleration, if i get the afformentioned upgrades and i want to reach about 55mph, with the stock speed being 45-50, my stock gearing is 13t front and 37t rear, if i go 15t and 35t what will happen, can the bike even pull that gearing comforatably, or should i only go for 14t and 36t.

let me know what you think, ill come up with more upgrade ideas later, feel free to chime in on other upgrades if your firmiliar with the subject

[RedRider_AK]

12.5:1 high compression pistons, which should be a nice improvement over the stock 9:1's what kinda fuel do i have to run, and what kina improvement will i see, any downside?

High compression will cause the engine to have more "acceleration" all around, because each power stroke will be more powerful. The downside is that you'll be producing more heat and may have to figure out a way to keep the engine from overheating...


highperformance cam, supposedly increases hp by 2, would be nice its only 70 bucks, what will i see from a mid- to high range cam, how hard is instalation and is it worth it

A cam will make the idle a little rough but will increase power pretty good (as long as the engine has a good air-filter and exhaust that will actually flow)


oil cooler, this bike is only air-cooled, and when i ride, i ride hard, seems like i need one, theres so many choices, $60 billet coolers, or 120 for radiator style, even 200 for high capacity, what should i get keeping in mind i plan on going with a 146cc bore kit in the future.

I have an SDG 107 (with a Honda 125 motor in it) and honestly, I don't know where you'd mount an oil cooler. Those inline billet coolers don't do squat as far as I know (I'm pretty sure they're only for coolant too...). I'd be looking at an oil additive (highlifter makes one I think)


and finaly on my list (for the moment) is a gearing change towards the top speed end, this bike has a crapload of torque and acceleration, if i get the afformentioned upgrades and i want to reach about 55mph, with the stock speed being 45-50, my stock gearing is 13t front and 37t rear, if i go 15t and 35t what will happen, can the bike even pull that gearing comforatably, or should i only go for 14t and 36t.

My friend has a Suzuki 160. His front sprocket (11t) wore out, so I slapped a Quadsport 230 sprocket on there (12 teeth). It lost almost all it's torque, it won't pull a wheelie even in 1st gear, but now 4th gear feels like 5th, and then you upshift into 5th and CRUISE at like 50 (stock top speed was ... 40 or so LOL). If I were you, I'd get a sprocket with a few less teeth on the back and leave the front untouched, IF you even do that. You'll need to do some other power-adders first, then regear it.

Something you haven't mentioned is porting/polishing. I think you ought to do that before anything else...

[honda_atc200es]

cool thanks for the info, as for the cooler, i have seen it on other bikes, i would hope it mounts somewhere being that the company that makes it also makes my pit bike i do belive that the hoses go into the right side of the engine and they give you a new plate with the cooler, that oil additive sounds cool, i saw it once before, how long do its effects last? from what you say about the cam, ill need a uni filter and an fmf 4.1 pipe, that pipe isnt cheap lol, so a cam may wait. about the poart and polish, how hard is that? i have read tutorials, maybe ill have my cousin do it for me

[RedRider_AK]

Porting and polishing. In theory it isn't hard. In practice, nothing is ever as easy as it sounds. I think you should practice on some junk cylinders/heads before you touch yours...

[honda_atc200es]

what kinda imrpovement could i see from a good port and polish

[RedRider_AK]

A whole lot more power. LOL.

[honda_atc200es]

lol, yea well im ordering some psitons and a cam soon, so i can do the port and polish while the engine is apart