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Discussion Starter · #1 ·
guys-

so i'm loosing my clearance between the valve stem and the rocker every time i run the bike....fuel spitting out the carb intake and really choppy everywhere. where should i start and what should i look for along the way?

i have tonight and next sunday to work on the bike before a weekend of races.

thanks so much-
tt
 

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Discussion Starter · #3 ·
matt-

yeah, i'm guessing it could be a worn valve stem that's getting longer...but it's been happening after short test rides. i suppose the valve could be warped too, or something's wrong with the seat? i have no real clue. oh, and i do check the valves between each race weekend and have never seen any significant changes.

so what i just did was take the clearance out from .002" to .004" since the .002 has disappeared three times now. i ran the thing around for ten or so minutes at high rpm and it ran on both cylinders and was mostly clean the whole time. it didn't feel very crisp though. it's cooling now and i'll check the clearance again in a bit.

thanks though, i'm thinking the transplant thing is going to be the answer.

-tt
 

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Discussion Starter · #5 ·
joe-

thanks. the mark on the intake rocker adjuster is in the right spot. on the exhaust, it's pointing down to 8o'clock? the rockers are independent though, right? also, what do the marks mean exactly?

wouldn't a broken spring lead to too much clearance between rocker and stem...instead of less and less?

-tt
 

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Discussion Starter · #8 ·
guys, thanks a lot-

jb, my car mechanic buddy was floating the idea of the "stretching" stem. he said that he's seen it but i don't understand how it could actually happen. this isn't a new head or valves, so the bent valve seems the most logical to me. the head is still all OEM with no replacements and i know the bike has been getting a little doggier since the end of last season. so i'll try to find a head and switch them out.

thanks again-
tt
 

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Discussion Starter · #12 ·
thanks-

it's early and i've got to get to work, but JB. i have been running on one cylinder (all through the FCB race even) until i went ahead and took the clearance out to .004" from .002" last night. then it ran on both and wasn't breaking up anywhere, but wasn't very crisp on the throttle either.

i'll start digging in tonight.


-tt
 

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Discussion Starter · #14 ·
guys-

thanks. i'll go through all this advise tonight. joe, it's cool, i've abandoned the magic stretch-armstrong stem idea....it wasn't mine and i didn't like it to begin with, but i just don't know much about the valves beyond their function.

off to blow some head-
tt
 

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Discussion Starter · #21 ·
really, thanks so much, i love you guys too-

anyway, i got down to the head, but won't be able to compress the spring until tomorrow. and since i'm right there, does anyone have a line on some new rings to fit the OEM pistons?

what i've seen so far: (jb, my camera is at the garden right now)

there doesn't look to have been any contact between the valve and the head.

the intake valve in question looks to have a face that's seating a little closer to the head than the "good" valve face. which i'm thinking doesn't differentiate anything...tuliping face or recessed seat or i suppose even a bent valve if it's not the same all around?

the other odd looking thing is that the spring seat looks like there could be a problem or just some rough machine work...thin little bits of metal where the spring seats are sort of rolling away from the spring...kinda like what you see on the underside when you drill thin sheet metal or aluminum too fast with a bit that's too big. there's some evidence of this at the base of the other springs, but it's more pronounced on the problem valve. but if the spring were digging into the head, i'd be gaining clearance instead of loosing, right?

the cylinders look pretty good, no ridges, no scoring but i'm burning oil on the right side which makes me think i should slap new rings in while im there?

anyway, chris i'll try to bring a sorted bike to summit.

night guys, and thanks again-
tt



Edited by - ttilghman on May 29 2007 11:16:11 PM
 

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Discussion Starter · #25 ·
bfd-

thanks i'll keep an eye on the guides.

joe-

stock pistons, but thanks. and i want to do every thing i can before i look for a loaner...i want to kick your fancy new bike's ass with my POS clapper.

-tt



Edited by - ttilghman on May 30 2007 12:11:47 PM
 

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Discussion Starter · #27 ·
guys-

springs are out. valve seat is just a floatin' around in there loose as can be. also the valve face is pretty wobbly warped. on the other side, the "good" intake valve just slipped right out of the guide once the keepers were off and i've been buring oil on that side....any chance that's where i was oiling instead of blaming the rings?

i just picked up a head from a CL350, it's the same head as the CB right, just a different cam? i guess i can compare valves as easy as anyone elese?

thanks again to all you guys, i'm sure i'll have more questions as i start to get things back together. i'll check the valves/springs/seats on the new head and lap them all in. what elese.

oh, and on the cam, the intake lobes show a bit of pitting and some discolorization at the tips. am i wearing through the heat treatment, nothing looks too bad to put back in but i don't really know anything?

thanks again-
tt
 

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Discussion Starter · #30 ·
monkey-

thanks for givin' me back my mojo. let's go later the lwsv grid next week.

EVIL, you win the prize. and i'm simply overjoyed i found this before it lit the fuse. i think i'll start drinkin'.

lonejaquar, i'm lookin' for you and that TEX boy.

3widemonday-
tt
 

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Discussion Starter · #34 ·
guys-

thank you all for the help. the bike is better than it's ever been. starts super easy, holds an idle, is crisp on the throttle though the whole rev range, and launched like it never has on a practice start. for those of you who've never seen the back of my bike, it has a solid gray bumpstop and i'll be wearing Rev-It leathers with a white helmet.

T1 bitches-
tt
 
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