XR680R Up and Running,,, BUT????

First off, thank you to everyone who has helped me with questions i have had while building my 680r.

So i started it up today for the first time after having it bored out to 102.4mm (making it a 680) done by millennium technologies (great quality work and service), with a wiseco 10:1 piston, an edelbrock carb, and a hotcams stage 2 cam, and a new timing chain and slider tensioner. I also cleaned and lapped the valves while i had it apart. It took quite a few kicks, but finally started up, i was worried that it wasnt going to pump oil, so i put oil everywhere i could think it would go, and it seemed to have worked out fine. i have been taking it easy to break it in, BUT i am a little worried about the sound i am hearing its a ticking noise in the top end somewhere, (sounds like an old sewing machine), i re-adjusted the valves, and it still does it... does anyone have any clues as to what this might be? Is the cam just breaking in? I put all this money into it, i would hate to wreck something.


Valves not to spec,too much free play?? Did you recheck the one with the deco system?

SET them at TDC and you'll be right,turning the crank the wrong way will give you the problem you have.

checked them three times, clearance seems fine intake 15, exhaust 20 right?, is it possible that the cam chain is slapping some how? i hope not, its brand new.

what do you mean by 15 and 2o

You have the left (chain side) exhaust valve loose. I do not set the valves at TDC but at the bottom of the lobes for the intake and the bottom of the lobes for the exhaust before the decompression engages or after it releases. You can tell the left exhast valve will get loose. You can see the lobes of the cam if you look. This should be the way the valves are ajusted but, Honda tried to make it easier for everyone and wrote the manual the TDC way.

Int 0.15mm +/- .02mm .006" +/- .001, Exh .20mm +/- .02mm .008" +/- .001

guess ill check them again, thats what i meant by 15 and 20, just too lazy to write the . and mm, sorry for the confusion

I adjusted them again, im such an idiot, i was using the .015 INCH feeler gauge on the intake side instead of the .15MM, i wasnt using inches on the exhaust side, just the intake side?? Wow with an idiot mistake like that im surprised the thing even runs after i put it together,,,,, musta got lucky.

By the way, this time it did work, she purrs like a newer quieter sewing machine, i may have to do a little more adjusting, but im on the right track!!

I cant wait until i get it broken in a little more so i can twist it to the stop and see what it does, hopefully she holds up.

thanks for the help

That's good to hear that's all it was. Dang metric system will get you everytime. LOL

Take care,


I will say this

after I had my XR680 supermoto built

I did notice the engine does make a different sound(then a stock one) also revs a little bit slower

but the power gain is phenomenal

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