How to make a TTR-125L GO Faster!!!!!!


Sep 30, 2000
I'm posting a question for my brother who has a TTR-125L...
Anyway, I was wondering, whats the number one upgrade he could make for his bike to make it have an overall faster speed (or at least seem like it does...) Would a BBR or White Brother's Exhaust be the trick? Let me know...

Rich Rohrich

Moderator / BioHazard
Jul 27, 1999
A $30 Powroll Thrust Chamber, rejetting and removing the airbox rubber snorkel will probably give you the best bang for the buck. A full exhaust system from companies like BBR, Powroll, or Engines Only will make a big difference in performance for a very reasonable cost.


Lifetime Sponsor
Mar 22, 2000
There are a half dozen TTR125's where we ride, we own 2. Dropping an after market pipe on with the aforementioned rejetting and airbox mod does make a pretty big difference. We have a PC T-4 pipe on one bike and an FMF on the other. We ride with folks that have the thrust chamber and the TTR pipe. All of the pipes seem to have similar performance gains. The FMF is a little stronger on the bottom and the PC is a little stronger in the mid and top. The only drawback is the sound level. The FMF is louder than stock, the PC is next loudest, both are tolerable, the BBR in our group is much louder than the other two. Check the prices too, there is a significant difference.


Apr 17, 2001
One of the best mods is flywheel machining mod. It doesn't go faster in top speed, it just gets there quicker. Pipes add a lot but $$$ more.


Mar 25, 2001
I suppose if you want to go faster try the 14 tooth front sprocket. I thought it made the bike easier to ride--first gear was almost worthless--but I'm a spode. I think it cost me 12 bucks. I also have the PowRoll Thrust Chamber--30 bucks. I drilled 6 quarter-inch holes around the exhaust opening into the spark arrestor to let the bike breathe better--free, and the spark arrestor still works. Take it off and you'll see what I mean. I cleaned out the airbox by removing the snorkel and drilling 2 one-and-a-half inch holes into the top--also free. Much better performance overall, but again, I'm a spode. I hope to get a #110 main jet tomorrow--about 5 bucks. For less than $50 it makes a difference. Then you'll have money left over to replace those weak fork and shock springs.


Aug 22, 2000
In dyno testing we found the Powroll Thrust Chamber actually gave a better overall horsepower gain than any complete system on a STOCK TTR 125.

Once engine modifications are done (bore kit, cam), then the complete pipe worked much better.