RM125 exhaust question

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5/16/2019 6:16 PM

I am building a 2003 rm 125 for a kid who is currently racing a kx 100. He is pretty inexperienced, only raced a few times, still not quite got the hang of keeping it on the pipe and sometimes shifts too quick. He is 14 and 125lbs. His dad had this 03 rm 125 in the barn and brought it to me to do a frame up build. I did the crank, clutch, etc. I have a V-Force 3 reed block for it and I am currently waiting for the cylinder to come back from replate. So my question is what pipe and silencer combo is best for this bike and this kid? Im thinking fmf fatty and shorty?


5/16/2019 8:21 PM

Fmf fatty works very well. PC is a bit pipey.


5/16/2019 10:10 PM
Edited Date/Time: 5/16/2019 10:10 PM

03 rm 125... bills pipes hands down


5/17/2019 6:58 AM

I had a Doma on mine and it ran well, I never compared it to anything else though and it was a 134cc.


5/17/2019 11:30 AM

I run a dep pipe on one of mine and like it, the other bike has an fmf fatty which is also good although I find the stock pipe is still a good pipe


5/18/2019 4:04 AM
Edited Date/Time: 5/18/2019 4:06 AM

Suzuki RM125 Baseline: It's hard to really pinpoint a shortcoming when talking about the RM125 As with any 125, though, we are always looking for more.Bill's pipe and silencer Fit: A / Overall Rating: B+ Comments: Bill's knows the RM and is always a contender with this bike. Bottom mimics stock, while the mid comes on with some clout and pulls ultrastrong before falling off on top. This is a good setup, but it requires you to hit your shifts right on the money.DEP pipe and silencer Fit: A / Overall Rating: A- Comments: Like the SST, the DEP system doesn't produce extra bottom but makes up for it as the ponies build in the mid. This is where the usable performance can be found. It takes the momentum from its strong mid and keeps it pulling into a very effective top and overrev. The DEP was among the three favorite choices in the test.Doma pipe and silencer Fit: A / Overall Rating: A Comments: Like several units, the Doma makes the bulk of its delivery in and around the mid. The Doma earned high marks because of its power characteristics. It comes on slightly sooner than some of the other systems, yanks through the mid and has decent top. It makes good power and delivers it in a way to extend each gear and continue to pull. The Doma topped the podium at the end of the day.FMF Factory Fatty with Titanium II silencer Fit: A / Overall Rating: B Comments: This was again almost identical to the FMF standard Fatty. Mid was slightly upped, while top and overrev were lacking.FMF Fatty with Titanium II silencer Fit: A / Overall Rating: B Comments: FMF builds a quality product with the RM125 Fatty, though power output is not as good compared with other combos tested. Bottom was on par with stock, while the midrange punch is improved and allowed the bike to be ridden more aggressively coming out of corners. Top-end pull was weak and only slightly boosted over stock.FMF Rev with Titanium II silencer Fit: A / Overall Rating: B Comments: Like some of the other units tested, the Rev churns out a bottom copied from stock, while most gains were centered in the mid. The Rev pulls harder than the Bill's up top but not quite as strongly compared to the FMF SST. The Rev finished around midpack during our test; good but not great.FMF SST with Titanium II silencer Fit: B+ / Overall Rating: B+ Comments: Even the SST system doesn't pack in anything lower in the power curve but adds a serious punch over stock in the mid. The SST revs out further than the FMF Rev, Fatty or Bill's. As long as you don't let the revs drop, this setup pulls for days.Pro Circuit Works with Factory Sound silencer Fit: A / Overall Rating: A Comments: PC did a great job with its RM125 exhaust. The power is very similar to the Doma's--great mid to top--with a crisp snap of the throttle. On and off the gas the PC is quick to respond and allows for fun in the entire usable power curve. The PC finished up on the leader board during this test and ended up as the system that went home with the bike.