motor swap ?????

[lilman]

thanks to everyone here! this site is great for info.its my sons first year racing quads. he has won the spring series placed 2nd at western canadian nats, currently running first in our fall series.
only one problem now they are saying if he wind the fall series he should be placed in our mod series. he would be alowed up to 110cc 2stroke but no larger than 125cc 4 stroke!how much horsepower can anyone get from the 125cc 4 stokes? the parents running the mods say they r runnin 13-18hp from their preds and etons??i am contemplating trying to put a ktm 1o5 2 stoke in it that should be lots of power. has anyone tried this swap?

[Ride1Rob]

If that's the route you're going to have to take I'd say go with a 2stroke motor. It's not a fair race running a modded 125cc thumper against a modded 110cc 2 stroke or even 90cc for that matter. For it to be fair the thumper would have to be at least 220cc to be in the same class as a 110cc 2 stroke. I have gone with the HC piston, 26mm carb, and portwork. Woke the bike up tremendously. I would say Jams bike is around 13hp range with those mods. With a bigger head/valves/cam and better exhaust the bike should easily do 18hp.

[JBOYZ]

I can't hardly see a 125cc 4-stroke even beginning to keep up with a 110c 2-stroke - that is not even fair.....

There is a lot of mods you can do to a 125cc 4-stroke - but the set up on the TY-125 really limits you.... Xtreme has a new 125cc 4-stroke motor they are trying out that does not have the duel clutch - that would be the motor to modify.....

Good luck.....

[hanzito]

thats why my son ran a 146 motor to keep up. but even then they would get him out of the corner if it was a good rider. but he pulls them on top because he can shift. for this season he will be on a yx 160. and will probably be running with some of my other buddys kids on blasters and 300ex because they all moved up from the mod 2 strokes in the mini mod class. and are all on 300ex and blasters now. my son isnt big enough to move up yet. he is a runt of a 10 year old. there was a 300ex and a lbaster that raced in the mini mod class last season and eh beat them both. but i dont think that either one was running right. i know my budy ricks daughter was on a modified lt80 and no any given night she and my son would switch places for first. and the lt80 flat out ran. and should would come intot he corner to fast by just letting off the gas. where my son would let off and compression braking would slow him down where as the lt80 just coasted and pushed her wide in teh corners of the flat track.