Valve check results

[evn_05]

Hey all,

Doing my winter maintenance in my shop this weekend. I spent the morning pulling all the jazz off the top of the motor to do the valve check. I did not pull the tank, actually just suspended it from a few eyelet hooks I have in my ceiling by a few ratchet straps.

In pulling the radiator I just drained all my coolant as it was brownish and smelled bad. Likely the original is my guess. The bike is right around the 26k mark for the valve check.

I have a fair amount of tools and a semi-heated garage so this went pretty well overall. I did have to buy a set of feeler gauges but I am sure I will find plenty of uses for them now.

So here's the skinny: All my valves were within spec except for two exhaust valves. Both my outside exhaust valves on cylinder #1 and #4 were loose. So that would be, if you were sitting on the bike, the left on #1 and right on #4. I pulled .38mm and .35mm on these two valves.

So they are loose, which with my past experience with 4t dirt bikes is much better than tight. I do, however find it odd that both outside valves are the ones that are out of spec. Not sure if there is a known machining issue with the cams on these bikes, specifically the exhaust cams? Or if it is just a pure fluke that those are my winners.

Now the decision is looming as whether I pull the cams and re-shim these guys are button it back up and call it a day...

Any thoughts or input would be helpful.

 

[ozgurakman]

brownish coolant is not something usual. maybe some oil in coolant? you would check the engine oil for any mixing. If I had this problem, I would check the oil and coolant. Then if any mixing ocurred, you should check the head gasket.

OR if previous owner mixed blue/green (usually Mono Ethylen Glicol) and red (usually silikate free mono ethylen glicol with organic acid inhibitors) coolant (this is something bad).

answer to your question:

you should check the co values imo. very left and very right valves shouldn't be off at same time or it's just a coincidence but I think co1 (for #1-#4 cylinder) is low and these cylinders are lean.
Did your bike has any nasty vibs? Did you checked the t.body sync?

 

[FinalImpact]

Hey all,

Doing my winter maintenance in my shop this weekend. I spent the morning pulling all the jazz off the top of the motor to do the valve check. I did not pull the tank, actually just suspended it from a few eyelet hooks I have in my ceiling by a few ratchet straps.

In pulling the radiator I just drained all my coolant as it was brownish and smelled bad. Likely the original is my guess. The bike is right around the 26k mark for the valve check.

I have a fair amount of tools and a semi-heated garage so this went pretty well overall. I did have to buy a set of feeler gauges but I am sure I will find plenty of uses for them now.

So here's the skinny: All my valves were within spec except for two exhaust valves. Both my outside exhaust valves on cylinder #1 and #4 were loose. So that would be, if you were sitting on the bike, the left on #1 and right on #4. I pulled .38mm and .35mm on these two valves.

So they are loose, which with my past experience with 4t dirt bikes is much better than tight. I do, however find it odd that both outside valves are the ones that are out of spec. Not sure if there is a known machining issue with the cams on these bikes, specifically the exhaust cams? Or if it is just a pure fluke that those are my winners.

Now the decision is looming as whether I pull the cams and re-shim these guys are button it back up and call it a day...

Any thoughts or input would be helpful.

Mine were sorta like that...
1 and 3, although it was both valves on hole #1, so 3 valves were out of spec enough to hear an audible "TAP" Tap tap.... Fix them if you have the cover off. Its just a few more bolts.

Exhibit A and a thread link --> Click image!


The reward is a mechanically quieter engine that pulls better and runs smother. Well worth your time while its apart!
Check out that WHOLE THREAD - Good info! PS - mine was at 20,### miles but I heard it tapping since 4k when I bought it!

 

[evn_05]

The coolant color gives me no concern. It wasn't milky so not oil or head gasket issues. Hard telling on a bike you didn't own for the first 24k of its life. It'll get flushed out and replaced with new and it will be the least of my worries. Hopefully.

After a night of deliberation, I have decided just to leave it. Since they are loose and not tight I see little to no issue with it.

I did, however follow the instructions of the sticky about vibrations to check your plug wires and caps.

I tested the resistance of the primary coil (both in spec), the secondary coil (both in spec), and the caps (no listed variance). The caps are listed at 10K ohms and all of mine were between 9.6 at the lowest and 10.7 at the highest.

I did apply dielectric grease to the connection between the cap and wire after cutting them back and fanning the wires out like mentioned in the sticky. Since I had all the jazz off the top of the head I also threw in a set of Iridium NGK's since they were so easy to get to.

I will be doing a TB sync in the next few weeks to see what it looks like. Otherwise things are shaping up quite well for this riding season.

Cheers,

-Evan

 

[Zealot]

The coolant color gives me no concern. It wasn't milky so not oil or head gasket issues. Hard telling on a bike you didn't own for the first 24k of its life. It'll get flushed out and replaced with new and it will be the least of my worries. Hopefully.

If you've gone through all the trouble to do a valve check and have most of the stuff out of the way, what's it going to hurt by checking and making sure?

 

[trepetti]

I figure I know the answer to this question from reading all the posts about valve clearance checking, but to make sure I'll just blurt it out......

Even though the manual says to remove the throttle bodies, I have not ever seen a reference to a forum member having to do so. I am planning to do mine this weekend (DAMN!...forgot to get a CCT gasket) and just want to make sure I have everything covered.

Has anyone actually followed the procedure in the manual?

 

[FinalImpact]

^^ Wasted energy.... That gasket is overrated as is the timing cover. The quality is very good. Grab one if in doubt tho!

 

[trepetti]

Thanks FI. Even if it drip it is an easy retrofit. It looks to me like you left the throttle bodies in place. Is that correct?

 

[FinalImpact]

Yes, left them in place. Just get the Narrow gauges. The 0.500" are too wide and it will double the time it takes to do it.

Also, don't hesitate to double check once you've made the rounds and be as accurate as possible. As in place 1/2 gauges together to increase accuracy if need be. It all depends what sizes you have to work with.