Buttermilk
04-16-2008, 11:01 AM
Hi,
I relatively new here. Mostly lurk and read the various postings.
Thought I'd share my latest dyno chart for my 250R.
My build:
1987 TRX250R
OEM cylinder with my own porting (~194-195 degrees Exhaust; ~128.5-129 degrees Transfer timing)
Wiseco Pro-Lite '86 style piston.
+4mm Long Rod crank (76mm stroke).
V-Force 3 reed.
98 CR250 carb boot port matched to the VF3's.
Keihin PWK 41.5mm Taper Bored carb.
'87 airboot with open K&N filter (no air box, just the airbox boot).
Pro-Design Cool Head.
Custom Cut dome with ~ 15.2:1 UCCR.
ESR TRX11 Center Mount pipe w/ ESR Silencer.
Dyna FS programmable ignition (not yet programmed).
I think that's most of the pertinent info. I've still got a bit more work to do yet. While on the dyno, I discovered that the axle bearings were shot, and later that day also discovered that the carb was not matched to the carb intake boot (there was ~ 1mm miss-match between the bored carb and the boot, most definately hindering the flow path...), which I think hurt my numbers a bit. Got the bearings fixed and the carb boot matches the bored carb now, so back to the dyno soon.....
56.40 HP with 34.56 TQ. running Track TeK TT111 fuel. Not too shabby for a 250R.
Last night at the local race track practice night (short track/TT) the little 250R ran pretty good.
I relatively new here. Mostly lurk and read the various postings.
Thought I'd share my latest dyno chart for my 250R.
My build:
1987 TRX250R
OEM cylinder with my own porting (~194-195 degrees Exhaust; ~128.5-129 degrees Transfer timing)
Wiseco Pro-Lite '86 style piston.
+4mm Long Rod crank (76mm stroke).
V-Force 3 reed.
98 CR250 carb boot port matched to the VF3's.
Keihin PWK 41.5mm Taper Bored carb.
'87 airboot with open K&N filter (no air box, just the airbox boot).
Pro-Design Cool Head.
Custom Cut dome with ~ 15.2:1 UCCR.
ESR TRX11 Center Mount pipe w/ ESR Silencer.
Dyna FS programmable ignition (not yet programmed).
I think that's most of the pertinent info. I've still got a bit more work to do yet. While on the dyno, I discovered that the axle bearings were shot, and later that day also discovered that the carb was not matched to the carb intake boot (there was ~ 1mm miss-match between the bored carb and the boot, most definately hindering the flow path...), which I think hurt my numbers a bit. Got the bearings fixed and the carb boot matches the bored carb now, so back to the dyno soon.....
56.40 HP with 34.56 TQ. running Track TeK TT111 fuel. Not too shabby for a 250R.
Last night at the local race track practice night (short track/TT) the little 250R ran pretty good.