Valve Adjustment

[emayn15]

I've set out on the adventure of shimming my valves for the first time. I've got all the clearances documented so now just on to the shimming part. Anyway when I took the carbs off I noticed there is a fair amount of a carbon looking substance built up on the backsides of the intake valves. Is this normal? Is there a way of cleaning them up without actually taking the valves out? It looks like it's a total PITA to go anyfurther then removing the camshafts/buckets and followers.

[stoinkythepig]

The carbon is easy to clean. Run a tank full of Techron treated gas through the engine under normal riding conditions and it will be gone.

Need to swap shims? I have a 7.48mm kit and can swap for ya.

[landricscustoms]

Spray carb cleaner into the runner and let it sit there for about a half hour. Then tip and drain while spraying into the runner to clear it out. That will eat the gunk away.

[emayn15]

The carbon is easy to clean. Run a tank full of Techron treated gas through the engine under normal riding conditions and it will be gone.

Need to swap shims? I have a 7.48mm kit and can swap for ya.

Yeah it looks like I'm running a 7.48. Don't know exactly what I need yet though haven't got the old ones out yet.

Yeah I might have to try that Techron stuff next year. You're not the first post that it works.

[emayn15]

Spray carb cleaner into the runner and let it sit there for about a half hour. Then tip and drain while spraying into the runner to clear it out. That will eat the gunk away.

Yeah. I thought of Carb cleaner but I don't think I'd be able to obtain the tippage to get it out. The engine is still in the frame. The intake ports are deep and at a steep angle.

[Stromper]

techron or seafoam don't worry

Note many times you can move shims rather than all new ones

[stoinkythepig]

Yeah it looks like I'm running a 7.48. Don't know exactly what I need yet though haven't got the old ones out yet.

Yeah I might have to try that Techron stuff next year. You're not the first post that it works.

Well the offer is out there. I used to swap them at a dealer, but none will do it anymore, so I bought a full kit of them.

[emayn15]

Cool thanks! I'll see what I actually need this weekend once I start shifting them around. I only have a few out of spec but I think I'm going to try to bring them all as close to the middle or as close together as possible.

[stoinkythepig]

Cool thanks! I'll see what I actually need this weekend once I start shifting them around. I only have a few out of spec but I think I'm going to try to bring them all as close to the middle or as close together as possible.

Don't aim for the middle, aim for the maximum clearance allowed. They get tighter over time and maximum clearance gives you more time between adjustments. I can go 30,000 miles before I need to adjust mine. It's a whole lot easier to check the clearance than it is to adjust it.

[ZX-12R]

And here is the ubiquitous Hot Cams shim kit: http://www.cyclebuy.com/shopping/hot...imkits_748.htm

[Kham]

And here is the ubiquitous Hot Cams shim kit: http://www.cyclebuy.com/shopping/hot...imkits_748.htm

nice man... thanks. i'll be checking mine this winter or maybe spring.

[emayn15]

The carbon is easy to clean. Run a tank full of Techron treated gas through the engine under normal riding conditions and it will be gone.

Need to swap shims? I have a 7.48mm kit and can swap for ya.

Stoinky, does this offer still stand? I finally got around to pulling the shims and have a list of what I'll need. Just let me know.

[Degsy]

Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_0_2 like Mac OS X; en-us) AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8A400 Safari/6531.22.7)

If you run techron through to clean the valves, clearances may change a little. Just bear that in mind.

[emayn15]

Haha. Awesome. I never took that in to consideration. Maybe I'll just let it be then considering I'm already in to the later stages of the valve adjustment.

[stoinkythepig]

Stoinky, does this offer still stand? I finally got around to pulling the shims and have a list of what I'll need. Just let me know.

Absolutely. Let me know what you need.

I don't think techron will affect the valve clearance. The deposits are clustered around the stem where the airflow is interrupted by the stem and the fuel droplets fall out of suspension and collect on the stem itself. I have never seen anything collect on the sealing surface of the valve or the head, that's where velocities are highest and the constant opening, closing and spinning of the valve will keep them clean.

[Degsy]

Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_0_2 like Mac OS X; en-us) AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8A400 Safari/6531.22.7)

Cool thanks! I'll see what I actually need this weekend once I start shifting them around. I only have a few out of spec but I think I'm going to try to bring them all as close to the middle or as close together as possible.

Don't aim for the middle, aim for the maximum clearance allowed. They get tighter over time and maximum clearance gives you more time between adjustments. I can go 30,000 miles before I need to adjust mine. It's a whole lot easier to check the clearance than it is to adjust it.

That may be why you don't see any carbon deposits on your valve seating area or seats. Its false economy to adjust valves to the largest possible gap. You are not helping the valves, head and piston have have a good working relationship if you leave valve clearances loose like that. Cam ramp, valve open duration and timing are all affected by valve lash. You are always better of going for the middle of the adjustment range unless it's a desmo in which case tighter end of the adjustment range is always better.

Length of time between adjustments is a minor concern when compared to slamming the valve into the seat and slamming the cam lobe unto the bucket for half of those 30k miles.

Just my opinion. And when I do a valve adjustment I clean the valves before or not at all.

[Degsy]

Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_0_2 like Mac OS X; en-us) AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8A400 Safari/6531.22.7)

And I do make a living by doing valve adjustments (amongst other things) so I might be somewhat biased.

[stoinkythepig]

Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_0_2 like Mac OS X; en-us) AppleWebKit/532.9 (KHTML, like Gecko) Version/4.0.5 Mobile/8A400 Safari/6531.22.7)



Length of time between adjustments is a minor concern when compared to slamming the valve into the seat and slamming the cam lobe unto the bucket for half of those 30k miles.

Just my opinion. And when I do a valve adjustment I clean the valves before or not at all.

What's the downside of running them like I do? I've got the cylinder head sitting on my bench (engine needs a new head gasket) with the cams out, and the buckets and cam lobes look fine after 90,000 miles.

[darkduc7]

limits are limits. as long as youre within them, who cares. some smart engineer dudes decided they were ok.

that being said, when i do my ducs, i set the opener clearances on the loose side, and the closer clearances on the tight side.

on regular style valves, i go right in the middle of the recommended clearances.

i think it just comes down to how we each break the logic down in our brains.