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Discussion Starter · #1 ·
Anybody done their valve adjustment?

Was it difficult?
Did you re-use the valve cover gaskets?

Advice and pointers would be appreciated.
 

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I did a V-Star 950's (same basic engine design and parent to the Bolt we get the SCR950 from.) and it's not terribly hard.
What's a bit time consuming is taking the gas tank off to get at the inspection covers to do the adjustment.
YouTube a few Bolt tank removal videos to get an idea if you want to begin or not.

Re: Cover gaskets.
The inspection caps are held in place with a few bolts and sealed with an o-ring.
Given our bikes aren't that old, the O-rings can be reused if not damaged.

A good quality feeler gauge is helpful. So is a clean engine.
Nothing is as upsetting as opening up an engine and have a chunk of debris drop in out of seemingly nowhere!

Here are some pics from the V-Star adjustment.
 

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Discussion Starter · #3 ·
Eddie,
Thanks for the info, didn't know they were O rings, that makes sense. I'm ashamed to admit it but just turned 24K and haven't looked at the valves yet. " if it ain't broke don't fix it" theory. I hope to get the valves accomplished this weekend and replace the head bearing next weekend. A little nervous about the head bearing though.
 

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If it makes you feel any better, my other bike survived this steering bearing clean & re-grease session!
The bike stood on the center stand with boards under the engine and a few hundred round of .40S&W in the trunk for "ballast".
That's Dan Roark, my long time friend and retired aviation mechanic in the completed photo.
I worked at his Mom & Pop m/c shop for 13+ years on my days off.
 

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Discussion Starter · #5 ·
I'm seeing all kind of horror stories about getting the old races out. Any thoughts or comments?
 

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I'm seeing all kind of horror stories about getting the old races out. Any thoughts or comments?
Poppycock! Don't be afraid to take on this job if you can read a service manual AND have the mechanical aptitude AND tools. If you're lacking in ANY of those departments, take her to a shop.
As far as the valve settings go, here's a general rule of thumb that I have followed for 40 years and 29 motorcycles. If the valves aren't noisy and the bike isn't lacking power, leave them alone! I have bought several new bikes and typically sell them when I get around 25k miles on them. I have never checked or adjusted valves on any of them. I don't think that modern bikes need as much attention as, say, maybe an old Triumph. That said, it is about time for a valve check and a head retorque! But, she is 40 years old! Just my opinion. Jevers
 

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(snip)
As far as the valve settings go, here's a general rule of thumb that I have followed for 40 years and 29 motorcycles. If the valves aren't noisy and the bike isn't lacking power, leave them alone! I have bought several new bikes and typically sell them when I get around 25k miles on them. I have never checked or adjusted valves on any of them. I don't think that modern bikes need as much attention as, say, maybe an old Triumph. That said, it is about time for a valve check and a head retorque! But, she is 40 years old! Just my opinion. Jevers
Careful with the quiet valve theory, especially on a bike like the SCR with screw/locknut adjustment. In spec, they make a little racket. As they tighten up, the noise subsides. Quiet valves are like quiet 3 year olds: They're up to no good! :grin2:
That said, modern metallurgy is quite good.
I've had several high-mile bikes come through the shop where the clearances had been set once and stayed pretty much in spec afterward. 7 of the 8 valves on my personal Yamaha 1200's were dead-on at the 1st inspection around 24,000 miles. One intake was like 0.001 out to the loose side. My veteran mechanic friend took one look and said, "Don't you dare pull that cam for that! It's fine! Leave it alone."
 

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Discussion Starter · #8 ·
Poppycock! Don't be afraid to take on this job if you can read a service manual AND have the mechanical aptitude AND tools. If you're lacking in ANY of those departments, take her to a shop. Jevers
I've got the manual and I believe I have the skills required, What specialty tools would I need?

Thx
 

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Discussion Starter · #9 ·
I've had several high-mile bikes come through the shop where the clearances had been set once and stayed pretty much in spec afterward. 7 of the 8 valves on my personal Yamaha 1200's were dead-on at the 1st inspection around 24,000 miles. One intake was like 0.001 out to the loose side. My veteran mechanic friend took one look and said, "Don't you dare pull that cam for that! It's fine! Leave it alone."
Any thoughts as to whether the SCR likes the valves loose or on the tight side?
 

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Poppycock! Don't be afraid to take on this job if you can read a service manual AND have the mechanical aptitude AND tools. If you're lacking in ANY of those departments, take her to a shop. Jevers
I've got the manual and I believe I have the skills required, What specialty tools would I need?

Thx
I believe the service manual will tell you exactly what speciality tools you will need.
 

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Any thoughts as to whether the SCR likes the valves loose or on the tight side?
Seeing how we don't have to play the "This shim is close enough" game, I'd just set them dead in the middle of the range. That's one of the cool things about screw & locknut adjustment. If they loosen or tighten, there's acceptable room.
 

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Any thoughts as to whether the SCR likes the valves loose or on the tight side?
Seeing how we don't have to play the "This shim is close enough" game, I'd just set them dead in the middle of the range. That's one of the cool things about screw & locknut adjustment. If they loosen or tighten, there's acceptable room.
Eddie. Don't you have a
" FRUNK " to attend to?!😜 Just kidding, my friend. I'm happy and grateful that you still share your knowledge with us! Jevers
 

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Discussion Starter · #13 ·
Eddie,
Here are a few pics of the job. I went with your train of thought on the adjustments. .10 on the intake and .25 on the exhaust. The book calls out .08 to .12 intake and the exhaust .22 to .26. I think I will get another set of feeler gauges and re do the exhaust. Mine only went in .5 increments. All that being said the hardest, most time consuming part of the whole job was getting it stripped down enough to get to the valves 😂.
When I do it again (next week) I will replace the o-rings, they were pretty flat and I’ll replace all the valve cover bolts. Their junk, almost twisted one in half.
Anyway after doing it once and learning how all the hose fittings and connections work, would I recommend someone else doing this? 🤔. Yeah, “if your gonna ride em you better know how to work on em” 😎
I will post again next week after the re-adjust and the head bearing project.
 

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Discussion Starter · #14 ·
One other thing I forgot to mention. I’m kinda a high mileage guy. Meaning I ride it more than I work on it. But, I changed the plugs at 12/K like the book said and never looked back, well they are only torqued to like 9.5 foot lbs or something like that and when I took them out to do the valves they came out with my fingers😱 weren’t tight at all.
Lesson here, check the plugs every 4/K like the book says 😂
 

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I owned a successive pair of Honda Transalps.
Major services went:
* Take everything off the bike except the center part of the main fairing.
* Oil & filter change
* Adjust the valves (exhausts were under round screw in caps and real ship-in-bottle-esque.)
* New spark plugs (4)
* Synchronize the carbs using a tiny lawnmower tank like an IV bottle.
* Clean and adjust the chain
* Put it all back together.
I got where I could do it in about 3 hours every 6k miles.
 

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Discussion Starter · #17 ·
OK, after much thought, I think I'm going to re-do these and set them both to the tight side. My reasoning is that they will open more and stay open longer thus getting more mix into the combustion chamber.
The intakes call out .08-.12 and the exhaust call out .22-.26 I think I'm going to set them at .09 and .23 respectfully. Any thought or reasons why this is a good or bad idea would be appreciated.

After 200 miles I can feel the difference in the bike, but I think it is mainly the spark plugs getting re torqued. :surprise:
 

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OK, after much thought, I think I'm going to re-do these and set them both to the tight side. My reasoning is that they will open more and stay open longer thus getting more mix into the combustion chamber.
The intakes call out .08-.12 and the exhaust call out .22-.26 I think I'm going to set them at .09 and .23 respectfully. Any thought or reasons why this is a good or bad idea would be appreciated.

After 200 miles I can feel the difference in the bike, but I think it is mainly the spark plugs getting re torqued. :surprise:
Exhaust valves in particular have a tendency to tighten up over time. Running them to the tight side could invite issues.
I'd leave them where you have them set presently and maybe stick some fresh spark plugs in it. NGK 3901 (standard) or 9198 (Iridium versions).
Since you adjusted the valves, the throttle body synchronization could be now off slightly due to vacuum differences created by the new valve openings. Getting that as close as possible will improve things a hair, too. Neither procedure requires the tank to come off, so it's fairly easy access.
 

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Discussion Starter · #19 ·
Eddie,
Thanks for the info, Didn't consider the throttle body sync. I'll have to look into that, after I finish the head bearings. I'm still going to revisit the valve settings this weekend, I will have put on over 500 miles. Curious if they remain constant. also got another set of feeler gauges, (graduate in .1 increments .08, .09, .10, .11 etc..)
 

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Discussion Starter · #20 ·
Exhaust valves in particular have a tendency to tighten up over time. Running them to the tight side could invite issues.
I'd leave them where you have them .
Eddie,
After further thought and talking to service techs at the local dealership, It seems that setting them both to the loose side is the correct way to go. It was explained to me that the valve stems actually stretch over time thus tightening up your tolerance.
 
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