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I need to tune my valves but don't know what measurements to go by, also how often do they need to be adjusted. I'm not sure how the process goes. If anyone out there knows, I'd really appreciate it if you could explain how to get it done. My engine is a 91 gsxr 750. Thanks a bunch everyone. I appreciate everything.
 

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I believe the service intervals are 4k miles (at least that's what I do on mine) though to be honest after the initial settling in period I think they tend not to shift much unless you run your bike really hard.

Get the Clymer manual before you start work. It's not too difficult but it would take a lot of time to write out the procedure and might not make sense without pictures. I think the books are like $20 or something. Also the book will have torque values for the valve cover bolts which are important otherwise you're almost guaranteed to strip them.

EZ Amazon link:

http://www.amazon.com/exec/obidos/ASIN/0892877634/qid=1022251395/sr=8-1/ref=sr_8_1/103-7539454-1283031

Matt
 

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Hey pacman, yes you really need a manual, I check my valve clearances every few thou miles, and use the manual everytime. Money well spent.

Steve S
 

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Definitely buy a manual, worth every penny. Also may want to invest in the special "Tappet Adjusting Tool Set" especially for Gixxer type valve adjusters. I did it without one of these babies and it's a pain in the ass. You'll see once you get in there... The tool allows you to tighten the locknut without affecting the clearance you've set. It took me twice as long without it cuz I had to go back and do each one at least twice to get the proper clearance.

The only place I've seen the tool is the Dennis Kirk catalog. P/N 28-461 for $41.99.

Good luck and be verrrryyy careful when tightening the valve cover bolts that you don't strip out the holes!
 

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Isnt 91 the first year they went to shim under buckets instead of adjustable tappets? If so, changing shims are a pain in the nutz! Get a service manual...
 

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Changing the shims is actually fairly easy. Just slide the rocker arm over and pull the shim out with a magnet. Getting the valve cover off, especially if it still has the air box, is where all of the time and effort comes into the job. Also, you could end up spending $100s on shims. I was counting the other day, and figured that between the three boxes of shims we have at the shop, we have over $2000 worth of shims. And we don't even have ANY of the FJ-style or KZ-style shims. It might end up being cheaper in the long run to just pay a reputable shop to do it for you.
 

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Discussion Starter #7
How much would you say is average for a shop to adjust them for you. I don't know much about the shims that you guys are talking about. I ordered a manual, and it should be here Thursday. That should help quite a bit. Do you just have to replace the shims or are the shims actually like a spacer that goes in there. Thanks a bunch everyone. I'm starting to realize the greatness of this site. It's amazing!!! I appreciate it.
 

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The others are correct. Get the Clymer's manual. And yes the 91 is "shim under bucket". 85-87 longstroke heads were adjustable tappet. I found that out when I put the 92 head on my 86. As for getting the correct shim...couldn't he check his clearances and order the correct set of thicker shims? It would mean down-time while waiting for the shims to come but you would save some money.
 

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Originally posted by flyinphill:
...It might end up being cheaper in the long run to just pay a reputable shop to do it for you.
<font size="2" face="Verdana, Arial">Reputable being the key - if you can find one. I got quoted $496 (Cdn) to adjust the valves on my 86 1100 (no shims needed)
. This is a job that took me as a rookie my very first time two hours including pulling the fairing, gas tank, etc. Hiway frickin robbery!!!
 

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As others pointed out this is a shim type head so no special tool needed. I haven't had to buy any shims in the 20K miles I've had my bike, like I said I think after a point they don't change much unless you're really hammering on it. What is probably worth investing in is a micrometer so you can measure the shims you've got. Sometimes you can fix problems by swapping shims between valves if you know what shims you have in all the valves (which is what I did one time) and if not a micrometer will make sure you get the right size shim so you don't need to do trial and error.

Matt
 
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