MBP Collets

[He Man]

Someone is selling a set of used 7mm collets. Was thinking about getting them for my bike. I remember someone said they arent as good as they claim it to be.

Are they just straight replacements? I have to do my 18,000 service ( at 17,300 right now and have free time)

[Christian]

Most of the folks I've talked to have gone with the "keep it stock" and "they aren't worth the hassle" route. I personally run stock collets and plan to indefinitely.

[junior varsity]

not a trivial install. useful if hitting high rpms often.

[He Man]

not a trivial install. useful if hitting high rpms often.

do the collets require you to get all new shims? or does it not change the measurement?

[mojo]

I'd imagine new collets would tighten up the measurements on the closing shims.  The original collets probably wear in and flatten a bit where the shim contacts it. 
I just did a valve adjustment on my bike, and 6 of the 8 collets were in pieces.  I just ordered stock replacements from Commonwealth.

[He Man]

heh. im afriad mine are broken to. The closer was within the new spec @12,000. so i let them be and sanded down the openers a bit. now im at 18,000 and the bike is running like absolute crap. but theres a lot of PM work i need to do. I havent changed oil in a while, and the clutch basket is worn to shit. etc.  got a lot of work to do next week.


anyway i bought them for $50. figure even if i dont need them, they are worth the cost since i might be needing new closers anyway.

[junior varsity]

yeah, if you got a deal, might as well throw them in. On the project 900 motor I've got, one or two of the half rings were broken, and I thought "GOOD! I was going to replace you anyway!"

[He Man]

 

I cant wait to do my valve adjustment. the bike is running horrible right now.  i almost hate riding it.

[Silver King]

  i almost hate riding it.

 Shhhhh!  She might hear you. 

[He Man]

Shhhhh!  She might hear you. 

who cares shes locked up right now.

[crimsoncloak]

At the rpms the 2-valvers hit, they don't offer much improvement.

If you have something that spins 12~13K, they are indespensible.  I did a whole season of trackdays with my 748 last year with no adjustments needed.  That includes plenty of 11K~12K thrashing, and big cams with oversize valves.  Would be a good choice for a S4 / S4R / S4RS if you like winding it out.

[junior varsity]

(or a 2V that's tuned up pretty high with race cams...  )

[He Man]

at $50. im not going to complain. if my half rings are broken since ive neglected them for so long, ill consider it a cheap alternative to the OEM ones. :p