toolucky Posted October 27, 2009 Report Share Posted October 27, 2009 I have the cheetah pv cylinders from trinity and right now they have a 230 main jet in them. Are there any adjustments on these because im not getting the low end out of these cylinders that everyone talks about. Mods are 19cc domes stage IV porting (ive been told this is Trinitys drag port) V3s, Dyna box on num 3 setting, 35 PWKs with clamp-ons, straight cut gears with hd clutch from kevin, lockup, all the trans mods, 15 41 gearing, with 22inch tires, Sheerer small bore OOF drag pipes. The motor is a 421 4 mill with 5 mill long rod 68.5 mm bore. Im doing alot of draging on the street and you have to rev it to the moon to make it launch without bogging. From a roll it halls ass but still seems to be lacking on the bottem. Almost forgot the carbs have 165 mains with plug chop, CEL needle on the middle clip and 148 pilot 2and1/2 turns out. Quote Link to comment Share on other sites More sharing options...
4stroker Posted October 28, 2009 Report Share Posted October 28, 2009 I have the cheetah pv cylinders from trinity and right now they have a 230 main jet in them. Are there any adjustments on these because im not getting the low end out of these cylinders that everyone talks about. Mods are 19cc domes stage IV porting (ive been told this is Trinitys drag port) V3s, Dyna box on num 3 setting, 35 PWKs with clamp-ons, straight cut gears with hd clutch from kevin, lockup, all the trans mods, 15 41 gearing, with 22inch tires, Sheerer small bore OOF drag pipes. The motor is a 421 4 mill with 5 mill long rod 68.5 mm bore. Im doing alot of draging on the street and you have to rev it to the moon to make it launch without bogging. From a roll it halls ass but still seems to be lacking on the bottem. Almost forgot the carbs have 165 mains with plug chop, CEL needle on the middle clip and 148 pilot 2and1/2 turns out. on the T-Rex cylinders with the RAVE type power valve, you can change the spring from lighter to heavier to adjust the power band. are the cheetah pvs the same? im assuming they are. take them apart and have a look. then find some stiffer springs to try in there. this will hold the PVs closed for longer creating more bottom end power. Quote Link to comment Share on other sites More sharing options...
toolucky Posted October 28, 2009 Author Report Share Posted October 28, 2009 on the T-Rex cylinders with the RAVE type power valve, you can change the spring from lighter to heavier to adjust the power band. are the cheetah pvs the same? im assuming they are. take them apart and have a look. then find some stiffer springs to try in there. this will hold the PVs closed for longer creating more bottom end power. Yeah there are springs inside of them. Maybe i will look into that and see if that will help my launch. Thanks for the reply Quote Link to comment Share on other sites More sharing options...
blowit Posted October 28, 2009 Report Share Posted October 28, 2009 Yeah there are springs inside of them. Maybe i will look into that and see if that will help my launch. Thanks for the reply Without riding your bike it is tough to call but it really sounds like you might be fighting a jetting problem as well. Hard to say if it is lean or rich but keep in mind that the main jet will have very little to do with your launch. Pilot, needle taper, needle position, slide cutway, will change that more. Sure sounds like you might be lean on the bottom. Typically when they start to get to fat, they still come out of the hole but blubber a bit. What I might do in your shoes is lock the PVs closed for now and concentrate on that bottom end. This will also help you work with jetting vs PV tuning. Yes, that setup should pull like a 4 stroke and be serious fun to ride... B Quote Link to comment Share on other sites More sharing options...
pabansheematt Posted October 28, 2009 Report Share Posted October 28, 2009 I have the cheetah pv cylinders from trinity and right now they have a 230 main jet in them. Are there any adjustments on these because im not getting the low end out of these cylinders that everyone talks about. Mods are 19cc domes stage IV porting (ive been told this is Trinitys drag port) V3s, Dyna box on num 3 setting, 35 PWKs with clamp-ons, straight cut gears with hd clutch from kevin, lockup, all the trans mods, 15 41 gearing, with 22inch tires, Sheerer small bore OOF drag pipes. The motor is a 421 4 mill with 5 mill long rod 68.5 mm bore. Im doing alot of draging on the street and you have to rev it to the moon to make it launch without bogging. From a roll it halls ass but still seems to be lacking on the bottem. Almost forgot the carbs have 165 mains with plug chop, CEL needle on the middle clip and 148 pilot 2and1/2 turns out. How old is the motor? The power valves got stickey on mine after about a year of use. I took both P.V.'s apart and cleaned them, problem went away. Also, your mains seem rich to me. I have a 492 cheetah 45 pilot, cel, 145 mains. Runs perfect. just my 2c Quote Link to comment Share on other sites More sharing options...
toolucky Posted October 28, 2009 Author Report Share Posted October 28, 2009 Without riding your bike it is tough to call but it really sounds like you might be fighting a jetting problem as well. Hard to say if it is lean or rich but keep in mind that the main jet will have very little to do with your launch. Pilot, needle taper, needle position, slide cutway, will change that more. Sure sounds like you might be lean on the bottom. Typically when they start to get to fat, they still come out of the hole but blubber a bit. What I might do in your shoes is lock the PVs closed for now and concentrate on that bottom end. This will also help you work with jetting vs PV tuning. Yes, that setup should pull like a 4 stroke and be serious fun to ride... B Thanks for the info....Ill try messing with the pilot and the needle clip. I was thinking that the needle might be a little rich but I will try lowering the clip first and see were it gets me. Quote Link to comment Share on other sites More sharing options...
toolucky Posted October 28, 2009 Author Report Share Posted October 28, 2009 How old is the motor? The power valves got stickey on mine after about a year of use. I took both P.V.'s apart and cleaned them, problem went away. Also, your mains seem rich to me. I have a 492 cheetah 45 pilot, cel, 145 mains. Runs perfect. just my 2c Whats your temp and elevation? Im at 850' and its been about 65 degrees here. The motor and pvs are less than a year and old. Quote Link to comment Share on other sites More sharing options...
stroking Posted October 28, 2009 Report Share Posted October 28, 2009 Whats your temp and elevation? Im at 850' and its been about 65 degrees here. The motor and pvs are less than a year and old. RICHEN UP the needle ONE CLIP and turn the timing up to +10 and hold on TIGHT!!! i have on that i just built and had the same lowend lag with +4timing....i turned it to +12 and WOW!!!....IT will flip completly over if your not careful on the launch.....but that motor runs alcohol so if your on race gas try +7/+10 Quote Link to comment Share on other sites More sharing options...
toolucky Posted November 6, 2009 Author Report Share Posted November 6, 2009 Ok guys i took your advice and richened up the needle one clip position, installed a chariot timing plate and set it at +5 with the Dyna on setting 1 and the bike does run better but it still has a bog seven out of ten launches. If it does launch it comes out hard and nearly turns over even with 7 inches over but its just not consistent. Any other ideas would be appreciated. Im still leaning towards power valve problems but right now Im just stumped. Quote Link to comment Share on other sites More sharing options...
AKheathen Posted November 6, 2009 Report Share Posted November 6, 2009 did you clean the powervalves? stuff can gum up pretty quick, especially if the jetting is off or having oil issues Quote Link to comment Share on other sites More sharing options...
toolucky Posted November 7, 2009 Author Report Share Posted November 7, 2009 Well I cleaned the powervalves and adjusted the pilot and the bike runs alot better, it even ran better with the plate at plus 5 and the Dyna on num 2 setting. BUT!! it still has a bog on the launch and if i do get it to launch without the bog it seems to sputter terrible through 1st and 2nd. What would happen if i just took the powervalves out and put a plate over them? Just an idea because im all out of ideas. Quote Link to comment Share on other sites More sharing options...
blowit Posted November 7, 2009 Report Share Posted November 7, 2009 Well I cleaned the powervalves and adjusted the pilot and the bike runs alot better, it even ran better with the plate at plus 5 and the Dyna on num 2 setting. BUT!! it still has a bog on the launch and if i do get it to launch without the bog it seems to sputter terrible through 1st and 2nd. What would happen if i just took the powervalves out and put a plate over them? Just an idea because im all out of ideas. As I previously suggested, you may want to pin the powervalves shut or all the way down so you can concentrate on your tuning without the addition of power valve tuning. Removing them all together will NOT work. You either have to pin them in the open or closed position. The problem is that as the valves open and close, it changes the required jetting so you are playing with jetting AND PV tuning. I have every confidence that you need stiffer springs in the PVs so they will stay shut longer but you also need to dial your jetting. One thing at a time... Brandon Quote Link to comment Share on other sites More sharing options...
toolucky Posted November 18, 2009 Author Report Share Posted November 18, 2009 Well just to update you guys, I've found my low end bog problem on my Good ole Trusty Trinity motor. Checked my squish and the piston wouldn't even put a blemish in the solder and the solder measures 1.30 so time to pull that F'n Trinity sticker off my plastic LOL Quote Link to comment Share on other sites More sharing options...
blowit Posted November 18, 2009 Report Share Posted November 18, 2009 Well just to update you guys, I've found my low end bog problem on my Good ole Trusty Trinity motor. Checked my squish and the piston wouldn't even put a blemish in the solder and the solder measures 1.30 so time to pull that F'n Trinity sticker off my plastic LOL Do you mean .130" or 1.30mm (.051") ? Remember those units... I think you are on the right track now... B Quote Link to comment Share on other sites More sharing options...
toolucky Posted November 19, 2009 Author Report Share Posted November 19, 2009 Do you mean .130" or 1.30mm (.051") ? Remember those units... I think you are on the right track now... B 1.30mm Quote Link to comment Share on other sites More sharing options...
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