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more power on my 650l....

By thumpin hard,
in XR600R & XR650R/L

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thumpin hard

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i am trying to decide if it is worth it to do more to get more power.

at this point it has been rejetted and has a white bros. pipe (back end only) and the smog removed.i want to be able to get third gear wheelies at speed without the clutch(probably not gonna happen)i have a fourteen tooth sprocket on the front.i would like to get more balls out of it but i prefer to keep the reliability and not spend a load as someday in a year or two i really want a aprilia motard i think.

any suggestions for extra power without getting crazy? maybe a cam? does changing the head pipe help much?thanks for the help guys!

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SniperTeamBravo

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i have been thinking of that,but i dont want to do something that will cost an arm and a leg..guess a should look into it..sigh..

A cam and big bore will totally make it rip and not affect reliability if done right. I'd also have the head ported while off the bike as the XR650L is a little lacking in the porting department. But it will totally rip...in fact,. if all you did was a Hotcams stage 1 or 2 cam it would give to a huge smile every time you ride it.

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thumpin hard

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a local shop said i could get a cam and a wiseco piston for uner 400..i have had bad experience with wiseco years ago...what about a ceramic coated piston? i hear these engines can get burned pistons on the back side from prolonged high rpm.would that help? i would rather not go the big bore kit..i mean i did an xl350 years ago and it was great..but i mean this is already a 650! geez...why not just get a 10.5 to 1 piston and a cam that will boost the mid and high end?

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martinfan30

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problem with the fatter cam is you lose the comp. release(auto comp. release), meaning you need a heavier starter. also needing hardened rockers, new springs and might as well valve job it. the higher (10.25 to 1 and up) pistons can cause a loss of "revability", is that a word? a larger header pipe does nothing for power(unless youve done piston, cam, porting) except lose backpressure and thus low end. keep it stock except a dyno jet kit, lose the air pump, k&n filter and a good muffler(white bros. e2) and youve got a strong brp. later!:mad:

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thumpin hard

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ok,now i am confused!...i have the jetting done,the white bros. pipe,the snorkle removed,a k&n filter,the smog is gone...but now i hear if i do a cam i will lose my auto comp release and then need a bigger(heavy,yuck!) starter?..sigh..besides in california the shops wont touch it so i have to do it myself,so i gotta do the right thing you know? i was thinking of doing just the cam and rejetting if necc. but now??!!

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XR650L_Dave

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I have not yet heard of someone going to an aftermarket cam without the decompressor and having a starting problem.

Even with a bump in compression, a more aggressive cam will have poorer cylinder filling at 'cranking speeds' and will in effect lower the compression, to a certain degree.

Mine's all stock in that regard, so take this with the appropriate grian of salt.

Dave

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thumpin hard

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on the hot cams version i beleive the auto comp. release is not a part of the new cam. hrc cam not sure. the more powerful starter is only a recomendation. check with xr's only to get the best info on this subject. sorry to confuse.

i dont know how the cam could have anything to do with the comp release...maybe i can get hold of the people who sell the "hotcam" and see what they say,anyway,thanks for the help!

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thumpin hard

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I have not yet heard of someone going to an aftermarket cam without the decompressor and having a starting problem.

Even with a bump in compression, a more aggressive cam will have poorer cylinder filling at 'cranking speeds' and will in effect lower the compression, to a certain degree.

Mine's all stock in that regard, so take this with the appropriate grian of salt.

Dave

yeah,i had an xl350 with a bigbore kit and cam and it started quite easily...thanks, i am guessing i could just do the cam and it would make quite a diff. and would not have a problem...but somebody correct me if they know for sure! eh?

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overrev

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the OE cam has an auto decompressor attached. the hot cam does not. without a substantial increase in compression, you dont need it(no starter upgrade necessary) it is designed to run with stock springs/valves/rockers.

DO NOT use hardened rockers. Hotams are new, not welded, use stock rockers. inspect the rockers for wear and/or damage,replace with stock, if necessary. you will need to remove the oil orifice and spring, from the head, which used to oil the auto decomp, on the OE cam. just drop it in, set to OE timing, set the valves to H/C spec, break it in and run it. (there is no stage 2 for the 650L, just S1)

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xgrhow

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I just got a hot cam, I don't know if it is stage 1 or 2. I got it from Cycle Gear, the info they had didn't say anything about the starter or anything. It did say it was made to work with stock valves and springs. I hope to have it on in the next couple weeks.

Where are you in California? I know some shops that will work on it for you.

Jerry Howell

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