Low RPM Sputtering

[vrtulnik]

.2 MM is still too small for the exhaust..


From my Yamaha shop manual:

View attachment 74374

Do you have a shop manual?

yes, i have... I am reading everything from service manual...

0.15 scale is accurate for exhaust valves... Something between 0.15 and 0.20.. 0.25 is too large - I put it there, but with more force. And 0.30 is impossible.

Intake clearances are within specs.

And this is strange, why it is only 0.20.. Just I know that cover was disassembled already... Maybe somebody adjusted valves few years ago. .

 

[TownsendsFJR1300]

Valves usually get tighter with age/mileage.

I did mine at 26,600 miles and had one exhaust valve, .001" too tight. The bike ran fine however,
I was there, did not want to risk a burnt valve. Yanked the exhaust cam (already had a shim kit) and adjusted. Good till over 50K miles.

Also, I'm not quite sure what you mean by quote:
"0.15 scale is accurate for exhaust valves... Something between 0.15 and 0.20.. 0.25 is too large"

If you intend to keep your valves tighter than spec's, okay, it's your bike..

*As we don't know EXACTLY the valve lash (not ball park) for your bike, I'd invest in another feeler gauge (as their super cheap), much cheaper than a new HEAD... Also, tight valves may be part/all of your issue. Skip over/ignore it, your pretty much chasing your tail.



My exhaust cam out for that .001" adjustment:

 

[trepetti]

Answers are RED.

(1) Crank set on TDC, (compression stroke #1 cyl), use the line next to the "T", get that dead nuts lined up with the mark on the block... That is your starting point.
= Crank is set on TDC (line next to T-mark against line on crankcase) - #1 cyl.

(2) Exhaust is next.. That should be lined up with the head(as you posted)-NO slack in the chain.
= Exhaust camshaft mark is 1mm above cylinder head. No slack in the chain

(3) Intake is last. That now(all slack out of the chain) should be on the mark.
= Intake camkshaft mark is 1mm under cylinder head. No slack in the chain


Note, chain stretch /wear could have the marks on the cam's NOT exactly line up.
If the / a cam is off a tooth, the marks would be significantly off for that camshaft.

Maybe this advice it too late, sounds like you got the timing marks aligned correctly.

But if you need to do it again, look at post #9 in this thread.... https://www.600riders.com/threads/help-with-my-timing-chain.59589/#post-644594

I had a terrible time getting things right last time I did it. But another member gave me his instructions and things went perfectly.

 

[vrtulnik]

Valves usually get tighter with age/mileage.

I did mine at 26,600 miles and had one exhaust valve, .001" too tight. The bike ran fine however,
I was there, did not want to risk a burnt valve. Yanked the exhaust cam (already had a shim kit) and adjusted. Good till over 50K miles.

Also, I'm not quite sure what you mean by quote:
"0.15 scale is accurate for exhaust valves... Something between 0.15 and 0.20.. 0.25 is too large"

If you intend to keep your valves tighter than spec's, okay, it's your bike..

*As we don't know EXACTLY the valve lash (not ball park) for your bike, I'd invest in another feeler gauge (as their super cheap), much cheaper than a new HEAD... Also, tight valves may be part/all of your issue. Skip over/ignore it, your pretty much chasing your tail.



My exhaust cam out for that .001" adjustment:
View attachment 74375

Reply to:
Also, I'm not quite sure what you mean by quote:
"0.15 scale is accurate for exhaust valves... Something between 0.15 and 0.20.. 0.25 is too large"
If you intend to keep your valves tighter than spec's, okay, it's your bike..

= No, i meant that my valve clearance is between 0.15 and 0.20mm. It is harder write exact value, so I wrote that 0.15 measuring plate goes easy to space between valve cap and cam - so 0.15 is "accurate". I apologize for misunderstanding.

I would like to adjust them for correct values.

 

[vrtulnik]

Maybe this advice it too late, sounds like you got the timing marks aligned correctly.

But if you need to do it again, look at post #9 in this thread.... https://www.600riders.com/threads/help-with-my-timing-chain.59589/#post-644594

I had a terrible time getting things right last time I did it. But another member gave me his instructions and things went perfectly.

Hi,

thank you for your reply.

I did not timing. Just today I removed valve cover and I found this "mistake".

I read this topic, because there is the same problem as I have. When I am reading #9 post it seems complicated for me. I have to read it more times (i am not native english speaker).

Although, when I will be adjusting exhaust clearances so I have to disassemble cam anyway.

 

[trepetti]

Hi,

thank you for your reply.

I did not timing. Just today I removed valve cover and I found this "mistake".

I read this topic, because there is the same problem as I have. When I am reading #9 post it seems complicated for me. I have to read it more times (i am not native english speaker).

Although, when I will be adjusting exhaust clearances so I have to disassemble cam anyway.

It seems complicated, but it was the easiest way for me to get it right. Keep it nearby and take your time reading it. Post any questions you have, we are here to help.

 

[vrtulnik]

It seems complicated, but it was the easiest way for me to get it right. Keep it nearby and take your time reading it. Post any questions you have, we are here to help.

Do i need remove CCT? Because I read that during adjusting clearances is enough uncsrew adjust screw in CCT for chain release.

 

[TownsendsFJR1300]

Do i need remove CCT? Because I read that during adjusting clearances is enough uncsrew adjust screw in CCT for chain release.

Yes, it has to removed to gain slack in the chain-to remove the cam.

 

[vrtulnik]

Yes, it has to removed to gain slack in the chain-to remove the cam.

I read about CCT, i do not understand installation steps. (already after adjusted valve clearance)

When is CCT removed, I need turn the tensioner rod fully clockwise with a thin screwdriver - whole rod will be in CCT housing. I will install the gasket and the timing chain tensioner onto the cylinder block and tighten the two timing chain tensioner bolts...

And than? How I stretch chain?

 

[TownsendsFJR1300]

^^^, correct.

Once it's in the block, it'll extend out automatically pushing the rear chain (fairly long)
guide up against the slack part of the chain- tightening it up..

Note, a brand new CCT assembly will already be wound tight and as I recall, Yamaha uses a pin/wire (don't re-call) that holds it in. Once in, you'd pull the pin and it would extend into the block.

Last time I did mine, I did exactly as you posted, hold the small, flat screwdriver to the unit, while wound up and then slip into the block. Hold it up against the block(it's now extended) and then put the two mounting bolts back in..


Below pic expires in 7 days




.

 

[vrtulnik]

^^^, correct.

Once it's in the block, it'll extend out automatically pushing the rear chain (fairly long)
guide up against the slack part of the chain- tightening it up..

Note, a brand new CCT assembly will already be wound tight and as I recall, Yamaha uses a pin/wire (don't re-call) that holds it in. Once in, you'd pull the pin and it would extend into the block.

Last time I did mine, I did exactly as you posted, hold the small, flat screwdriver to the unit, while wound up and then slip into the block. Hold it up against the block(it's now extended) and then put the two mounting bolts back in..


Below pic expires in 7 days

View attachment 74376


.

Yes, now I understands, thank you

 

[vrtulnik]

^^^, correct.

Once it's in the block, it'll extend out automatically pushing the rear chain (fairly long)
guide up against the slack part of the chain- tightening it up..

Note, a brand new CCT assembly will already be wound tight and as I recall, Yamaha uses a pin/wire (don't re-call) that holds it in. Once in, you'd pull the pin and it would extend into the block.

Last time I did mine, I did exactly as you posted, hold the small, flat screwdriver to the unit, while wound up and then slip into the block. Hold it up against the block(it's now extended) and then put the two mounting bolts back in..


Below pic expires in 7 days

View attachment 74376


.

I am posting photos of intake valves. You can see how are dirty. Carbon is on all valves.

****Better view is on second photo.

Question:
When I have open intake valves on #1 cylinder, another intake valves should be complete closed?

You can see on the second photo that valves on #2 cylinder are not complete closed.

#1 cylinder


#2 cylinder

 

[TownsendsFJR1300]

That one valve seat in the second pic looks pretty bad..

Re the valves, if intake rockers are(looking down from above) pushed open for that cylinder, their open and exhaust would closed.. Vice versa.

I suspect if you put seafoam, or some other carbon remover/liquid, it'd go right past that valve into the cylinder... That liquid, with all valves closed should just puddle up and NOT LEAK out..

I would be doing a compression test or better yet a "leak down" test.. You appear to have some definite carbon build up/leaking valve issues (just looking down the port).

.

 

[vrtulnik]

That one valve seat in the second pic looks pretty bad..

Re the valves, if intake rockers are(looking down from above) pushed open for that cylinder, their open and exhaust would closed.. Vice versa.

I suspect if you put seafoam, or some other carbon remover/liquid, it'd go right past that valve into the cylinder... That liquid, with all valves closed should just puddle up and NOT LEAK out..

I would be doing a compression test or better yet a "leak down" test.. You appear to have some definite carbon build up/leaking valve issues (just looking down the port).

.

Yes, it is not good new for me. I am thinking few days how can I clean them without remove cylinder head..

1. I will to pour Techron mixed with petrol (e.g. 1:5, or 1:10) into closed valves.
2. After 10-15 minutes I will try scrape carbon via brush. (I hope that valves will tight and liquid does not leak down..)
3. I will pull out liquid with syringe with hose from valve.
4. If there will be dirt, i can use vacuum with tube.
4. If it help - carbon will be removed from surface of valve, i can open valve and spray liquid on valves again, but liquid should will get into valve seats.

Maybe it is naive idea, but i trust Techron liquid will help me.



I don't know in what state are exhaust valves...

 

[vrtulnik]

That one valve seat in the second pic looks pretty bad..

Re the valves, if intake rockers are(looking down from above) pushed open for that cylinder, their open and exhaust would closed.. Vice versa.

I suspect if you put seafoam, or some other carbon remover/liquid, it'd go right past that valve into the cylinder... That liquid, with all valves closed should just puddle up and NOT LEAK out..

I would be doing a compression test or better yet a "leak down" test.. You appear to have some definite carbon build up/leaking valve issues (just looking down the port).

.

Hi,

1. valves adjusted - intake valves were 0.20 - 0.24, but left exhaust valve #4 was 0.38, ... Now, all valves are okay and adjusted!!
2. Carbon from intake valves - cleaned.
3. I had disassembled throttle body (where are 4 air (needles) screws). Needles were very dirty. Also I disassembled idle screw, and cleaned chamber.
4. I exchanged fuel filter.
5. TPS is new and adjusted.
6. I did TBS. Vacuum is about 8 inHG (i have manometers) it is harder to synchronize, i don't have carbtune.


Problem still persists. However sputtering during idle rpm is only under approx. 75 C... When bike is warmed, it is okay.

Bike is going much better, no vibrations, better sound. Very good, but problem is not solved.

Do you have any idea???

If there was a problem in intake hoses, sputtering will be also in higher temperatures, or no?

Thanks.

 

[TownsendsFJR1300]

If there was a problem in intake hoses, sputtering will be also in higher temperatures, or no?

Thanks.

I close inspection should show something.

Carb cleaner (or brake cleaner) sprayed around those boots, while the bike is idling, would make the idle rise IF THERE WAS A LEAK in the boots..

I wouldn't be concerned about the manifold pressure per say... As long as their within spec at idle(with in 10mm's) and preferably up to 4K RPMs you should be fine.

Pic of my carb tune after I re-adjusted the one exhaust valve:

 

[vrtulnik]

I close inspection should show something.

Carb cleaner (or brake cleaner) sprayed around those boots, while the bike is idling, would make the idle rise IF THERE WAS A LEAK in the boots..

I wouldn't be concerned about the manifold pressure per say... As long as their within spec at idle(with in 10mm's) and preferably up to 4K RPMs you should be fine.

Pic of my carb tune after I re-adjusted the one exhaust valve:View attachment 74430

Thank you.

Is it possible start bike without airbox? I can connect temp sensor. I would like spray brake cleaner around throttle body boots and another intake hoses.

- I checked air box boots, there was any glue, so I removed glue (because it was not tight) and I applied black silicone (for motors).
- Hose clamps on air box boots did not fit correctly, because were moved.

 

[TownsendsFJR1300]

Yes, you can start the bike with the box off as you need access to the boots.

I don't quite understand, you found someone put sealer on the boots?

 

[Gary in NJ]

Never use sealer on the boots. It will find its way into the engine.

 

[vrtulnik]

I don't quite understand, you found someone put sealer on the boots?

no, boots are glued on air box from factory. You have it too. This glue was cracked and I gave there silicone... It is good now, 100% sealed...


- I tried start bike without air box and sprayed brake cleaner - no sound change.
- I changed all intake hoses and TBS hoses...

I adjusted TBS screws as were before (I marked it), #2 cylinder has lower vacuum, about 1.5 inHg lower than another cylinders.

If I want synchronize throttle body and I want the same values on all cylinders, #2 screw is fully screwed. And also, when I have synchronized all cylinders, bike starting is harder.


When I bought bike, i have idle approx. 600-700 rpm. I could not changed idle speed with idle screw, so I adjust this stop screw:

Now i don't know in what position was this screw. Yes, i see wthite mark, but When I adjusted screw to white mark, i could not start bike...