- Joined
- Oct 12, 2009
- Messages
- 11,108
- Reaction score
- 4,069
- Location
- Cape Town
- Bike
- Triumph (all models)
I am quite often asked what modifications work and what don't .
Jaco and I had lengthy discussions about different modifications and we decided on a few basics , XR's respond well to higher compression so a 10.5:1 piston went in , of course extra capacity never does much harm so we made sure it was a 671 piston kit , 3mm oversize , anything more requires resleeving which we weren't keen on .
Of course to help that work a bit more efficiently a mild Megacycle cam was thrown into the equation . Then to finish it all off I cleaned up the head a bit , nothing radical and modified the airbox a bit more , that was pretty radical .
The bike originally had an FMF Hi Flo header with an FMF Power Core 4 silencer along with the normal carb modifications , airbox snorkel in the bin and the desmog treatment . The bike ran well , good smooth and strong acceleration but it wouldn't lift its front wheel as easily as Buddy's similar XRL , difference being that Buddy runs the FMF Power Bomb header .
Saturday we put Jaco's bike on the dyno after it had been run in , horsepower gain of 6.75hp ( 17 % ) and torque increased 9.5 Nm ( 19 % ) , and that was without sorting out the jetting , as it is the bike is running a bit lean . Reason for not sorting out the jetting just yet is because I am fitting another carb in the next few days , but I am sure that there is another 1 to 2 hp still there with the original carb .
Jaco and I had lengthy discussions about different modifications and we decided on a few basics , XR's respond well to higher compression so a 10.5:1 piston went in , of course extra capacity never does much harm so we made sure it was a 671 piston kit , 3mm oversize , anything more requires resleeving which we weren't keen on .
Of course to help that work a bit more efficiently a mild Megacycle cam was thrown into the equation . Then to finish it all off I cleaned up the head a bit , nothing radical and modified the airbox a bit more , that was pretty radical .
The bike originally had an FMF Hi Flo header with an FMF Power Core 4 silencer along with the normal carb modifications , airbox snorkel in the bin and the desmog treatment . The bike ran well , good smooth and strong acceleration but it wouldn't lift its front wheel as easily as Buddy's similar XRL , difference being that Buddy runs the FMF Power Bomb header .
Saturday we put Jaco's bike on the dyno after it had been run in , horsepower gain of 6.75hp ( 17 % ) and torque increased 9.5 Nm ( 19 % ) , and that was without sorting out the jetting , as it is the bike is running a bit lean . Reason for not sorting out the jetting just yet is because I am fitting another carb in the next few days , but I am sure that there is another 1 to 2 hp still there with the original carb .
