Posts
2408
Joined
11/2/2011
Location
Chapin, SC
US
Edited Date/Time
12/24/2017 8:25am
After a few rides on my 17 TC 250, I want to make the power more usable (vet intermediate MX skill level by the way.)
To me it feels like the bike hits hard, a little late, but then it's just done..... and that's even after being on a 125 for the past season I'm hoping to trade some of that mid hit to get it on the pipe earlier and smoother, and ideally get some more over-rev. I already went to a 49T rear to get longer pull.
From reviews it looks like PC and FMF both build power a little lower so that the hit isn't as pronounced, I was just wondering if anyone could share their observations of either pipe? I don't want to go full-on trail with the Gnarly because I still want top end.
Also... has anyone tried the green powervalve spring? I know it only makes a difference above 5500 RPM, so it isn't going to give me what I want, but I'm thinking a longer powervalve opening window may make that upper power more usable? I've been playing with the yellow one in a few different spots, currently I'm at about three turns in.
Oh... and I don't like flywheel weights, and I tried the mellow map but I felt like it took away too much bottom end. So really just looking for thoughts on pipes? Thanks!
To me it feels like the bike hits hard, a little late, but then it's just done..... and that's even after being on a 125 for the past season I'm hoping to trade some of that mid hit to get it on the pipe earlier and smoother, and ideally get some more over-rev. I already went to a 49T rear to get longer pull.
From reviews it looks like PC and FMF both build power a little lower so that the hit isn't as pronounced, I was just wondering if anyone could share their observations of either pipe? I don't want to go full-on trail with the Gnarly because I still want top end.
Also... has anyone tried the green powervalve spring? I know it only makes a difference above 5500 RPM, so it isn't going to give me what I want, but I'm thinking a longer powervalve opening window may make that upper power more usable? I've been playing with the yellow one in a few different spots, currently I'm at about three turns in.
Oh... and I don't like flywheel weights, and I tried the mellow map but I felt like it took away too much bottom end. So really just looking for thoughts on pipes? Thanks!
Thinking of going to 49 tooth, can you expand on how it helped tame the hit? I generally don't use 2nd gear, even on sand tracks, tend to use 3rd and 4th.
The Shop
This is a good read. Some info on the PC pipe.
https://motocrossactionmag.com/build-husqvarna-tc250-two-stroke/
http://m.vitalmx.com/forums/Tech-Help-Race-Shop,42/18-TC250-updates,133…
This bike hits hard, no matter what
17 TC 250, Vet C 50 y/o.
Went 49 on the rear sprocket, not much diff.
Played with pipes/silencer and settled on FMF HVA Fatty + Powercore 2.1 Ti (bazooka- 4stroke look!)
The pipe lessened the hit (OEM hits hard) and the broaden power delivery was noticeable.
I tried a PC silencer (regular 304) and like Opyguy can attest it helped over rev.
but the fit was total junk and l have it on a shelf now.
Constant tinkering with jetting on the TMX had me finally pulling the plug on a Keihin.
Best $ spent by far. The clean and consistent jetting actually smoothed the hit and really helped the low/mid transition
The TMX had a rich/lean not so clean feel that I could not get eradicate.
I think fast/skilled riders don't notice it because they're a lot more on the pipe, away from that hit point, always keeping momentum.
Added FWW - running "mellow" (?) map (could not really tell diff with the other one)
Played a lot with PV springs/pre-load
Red at ~ 1.5/2 in very responsive from low to mid but I found it sketchy on slippery soil
Yellow at ~ 2.5 turns in feels quite good
Just tried today the Green one at 2.5 and it was almost a toss compared to the Yellow
This is a very potent engine, and a bit of a handful for me at time.
I went away from 450's due to their "too much" nature but now that the engine runs real good I'm finding myself in trouble as the damn thing wants to bite me...
But I still think it's a fun bike and by far one of the best I owned, Just need to ride more and hit the gym more often
5.0 slide
44-73 needle in 3rd clip position (comes with stock kit)
S-1 needle jet (stock)
450 main (comes with stock kit)
30 pilot
This is for 75-85 degrees
500ft above sea level
15%ish humidity
Pit Row
Have also tried 14/49, 14/50, 14/51 gearing. Going to try 14/48 gearing next as bike is too responsive with 14/50 and 14/51, and not long enough with 14/49. 14/51 is nice in that I can stay in 3rd gear almost everywhere. Still not quite right though.
Have the stock pipe/silencer on mine now, but recently bought a Pro Circuit setup in order to get some additional over-rev. Hope that doesn't turn out to be a waste. Will report back after testing.
A buddy has an FMF setup and his doesn't hit quite as hard and revs out a bit further than stock.
My riding elevations are 0-500 feet above sea level, the coldest I ride in is the high 30s, highest around 90. Think the 30 pilot would still be the way to go in summer, maybe I will go a step richer for the winter to account for the cold?
My bike also makes a 'ting ting' noise / ignition when I let off of the throttle, instead of returning straight back to idle. Is that also be caused by the rich pilot?
The forks were impressive!
Post a reply to: 17-18 TC/SX 250 Pipe Comparisons