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here are some available h/p #'s out of the 650L

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CMRC, what do you have to do to change teh advance curve on an L? Apart from what works for RR, is there a solution that would be reliable for off-road use?

BP

which is the faster motor btwn the XL and XRL?

I havent had the chance to test back to back. But, looking at the head's there is a version of the XL which has twin 32mm inlets as standard - and this is the ones Ive started to tune. It looks to have bags more scope for porting than the XRL, without having to remove serious amounts of metal and do much or any welding.

Comparing the cranks, the XL crank is nicer. It has wasted sections to the flywheel web forgings to make it lighter and it runs a lighter balancer shaft. I think this is one of the main reasons a stock XL will tend to outgun a stock XRL even if they run out of go at similar speeds. The XL crank just seems to have a more refined classier finish about it, even the balancer shaft is tidier. Maybe it was made before Honda really started to get the cost out of the engine parts.

Id love to use a head like Stepho's gator but I havent really got the time or money to be making such big changes to the intake shape. Maybe one day eh!

This weekends job is to start wiring up the MSD ignition so I hope that gives a few more top end HP as well as the midrange power improvements Im sure it will bring.

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Im going to run the bike on the dyno and iteratively advance/retrad the ignition to get the bets power and powerband width. Im hoping it will also help starting.

It is possible to relocate the pickup but the main problem with the standard pickup is the steel pulser dog on the crank is too narrow to give a good spread of advance options. I plan to weld the dog up on the leading edge to give me the option of upto 45 degs of advance even if I dont use it all.

Given that the standard curve is full advance, 31 degs at 4000rpm itll be interesting to see what benefit there will be after progamming the ignition to usit my modded engine.

Once Ive finished building my sons model railway for xmas I'll have the time to test it!! :banghead:

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Hi all

I am searching for a camshaft for my 1986 XR600R. Can anyone help me locate one please. Thanks

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Start a new thread instead of resurrecting a three-year-old one that has nothing to do with your question.

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Start a new thread instead of resurrecting a three-year-old one that has nothing to do with your question.

Trauma, how often do you change your avatar?

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Trauma, how often do you change your avatar?

It depends on what I find to use. Sometime I change it a few times every seven days, but generally every one or two weeks. :ride:

Keep on truckin'....

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Start a new thread instead of resurrecting a three-year-old one that has nothing to do with your question.

Kinda harsh on the noob there, don't ya think?

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