Got the bike back from the dealer and she is still not right!

[HDKILA]

Just picked the bike up from the dealer. I brought her in earlier this week to get the carbs cleaned and checked. I was almost 100% sure this would cure my high rpm miss that I have posted about the last few weeks but it did not. I wanted to get ANY advice on what to check next....here is what I have done so far...

1. Pulled the tank and had it cleaned and epoxy'd

2. New spark plugs and checked the wires

3. New air filter/fuel filter

4. Had carbs cleaned and serviced by Yamaha

The bike is running great up until 7-8Krpm range.

The bike will not display the problem all the time and seems to not be doing it in first gear anymore.

It is definetly an intermittent problem.

I have a feeling either vaccuum or electrical.

HELP! Illinois does not have too many days of riding left in her this year.

 

[HDKILA]

I just noticed that the bottom of my airbox has a crack out of the smaller plastic hole that comes out of it. Also is something supposed to be attached to the smaller hole on the bottom of the airbox? I know the larger one has the rubber line connecting to it but what connects to the smaller hole?

 

[Storloc]

Nothing connects to the smaller one, not even sure what Yamaha had in mind for it to be honest.

Lets assume Yamaha actually cleaned and set up your carbs correctly. I would replace the plug wires as they tend to corrode and break down over time and its one of the few things you have left to try.

Oh and you might check the sync just for grins.

 

[HDKILA]

Nothing connects to the smaller one, not even sure what Yamaha had in mind for it to be honest.

Lets assume Yamaha actually cleaned and set up your carbs correctly. I would replace the plug wires as they tend to corrode and break down over time and its one of the few things you have left to try.

Oh and you might check the sync just for grins.

Plug wires are new and synch is spot on.

 

[RagingMain]

Do you have stock coils? I have heard that aftermarket coils can cause misses at higher RPMs.

Also check for vacuum leaks. Take some starter fluid (becareful of the paint) and while the bike is running spray some around the intake, v-boost boots, carb boots, air box etc etc. If the rpm go up presto you have a vacuum leak where you just sprayed. Might be a small one and get bigger the faster you go.

Also check the rubber hose coming from #2 cyl to the ignition advancer. If you have a vacuum leak there you wont be getting the proper advance and might have some issues.

If you have the tech manual check the advancer unit and make sure it is working properly.

You could always keep your bike under 7k rpm:rofl_200:

Cheers

 

[HDKILA]

Do you have stock coils? I have heard that aftermarket coils can cause misses at higher RPMs.

Also check for vacuum leaks. Take some starter fluid (becareful of the paint) and while the bike is running spray some around the intake, v-boost boots, carb boots, air box etc etc. If the rpm go up presto you have a vacuum leak where you just sprayed. Might be a small one and get bigger the faster you go.

Also check the rubber hose coming from #2 cyl to the ignition advancer. If you have a vacuum leak there you wont be getting the proper advance and might have some issues.

If you have the tech manual check the advancer unit and make sure it is working properly.

You could always keep your bike under 7k rpm:rofl_200:

Cheers

Where is the ignition advancer? I sprayed the starter fluid around all the appropriate areas and still no dice.

 

[RagingMain]

On cyl 2 (front left) there is a rubber hose that attaches to the advancer. you have to remove this hose when you sync your carbs. Follow it up underneath the air box. You will see it

 

[maxcruiser]

How about the rubber covers that plug the vacuum inlets (the ones you take off to sync carbs) Do they seal right or is the rubber hard from age - might be sucking air in from there/

Mike

 

[HDKILA]

How about the rubber covers that plug the vacuum inlets (the ones you take off to sync carbs) Do they seal right or is the rubber hard from age - might be sucking air in from there/

Mike

those are good to go. i am going to check the coils. i am looking at the manual and am confused on where to put the + and - leads to test them...any advice?

 

[maleko89]

To test primary side just stick them in coil connector. For secondary side stick positive up in plug boot and negative to frame ground. Should equal resistance of plug boot plus secondary windings or 18-19 KOhms.

 

[RagingMain]

To test primary side just stick them in coil connector. For secondary side stick positive up in plug boot and negative to frame ground. Should equal resistance of plug boot plus secondary windings or 18-19 KOhms.

Mark it is actually 23Kohms when combined all together between plug boot and secondary windings
Cheers Brounk:

 

[HDKILA]

To test primary side just stick them in coil connector. For secondary side stick positive up in plug boot and negative to frame ground. Should equal resistance of plug boot plus secondary windings or 18-19 KOhms.

I'm getting 3.1-3.2 on primary side. On secondary side I am not getting any reading on any of the coils. I think I am doing it right as I have disconnect the plastic twist that connects to the coil and stuck the positive lead in there and the negative to ground spots on the frame.

????

 

[RagingMain]

I'm getting 3.1-3.2 on primary side. On secondary side I am not getting any reading on any of the coils. I think I am doing it right as I have disconnect the plastic twist that connects to the coil and stuck the positive lead in there and the negative to ground spots on the frame.

????

Keep your coils connected to the wiring harness. Measure the resistance from the spark plug boot to the negative wires near the battery, or any where on the frame but you get the best reading where there is a negative ground wire.

 

[HDKILA]

Keep your coils connected to the wiring harness. Measure the resistance from the spark plug boot to the negative wires near the battery, or any where on the frame but you get the best reading where there is a negative ground wire.

I've tried this before and gotten the 22.8-23.1 reading on all 4. This is turning out to be a real stumper. I also checked the ignition advance rubber hose and thats good to go.

Any other ideas?

 

[m-cman]

I suspect the dealer didn't do that good a job on the carbs. :confused2:

 

[HDKILA]

I suspect the dealer didn't do that good a job on the carbs. :confused2:

I don't know....The bike seemed really crisp when they gave it back to me and the problem is happening right around the same rpm. I just don't get it.

 

[naughtyG]

I would take it back to them and explain that you're still having the exact same problem you gave it to them to fix - they should have another look at no charge since they didn't fix it the first time round!

 

[HDKILA]

I would take it back to them and explain that you're still having the exact same problem you gave it to them to fix - they should have another look at no charge since they didn't fix it the first time round!

At this point I think it's time to send them to the real expert...good ol Mark. If they come back good from there then I know it's not a carb problem and if they get there and he tells me there all jacked up (and he doesn't mind) I can go to the dealer with that.

 

[maleko89]

Mark it is actually 23Kohms when combined all together between plug boot and secondary windings
Cheers Brounk:

True with stock boots. I'm running NGK.

 

[HDKILA]

I just drained my floats and there is black shit coming out still! ARGGHHHH!

I just paid 400 fucking dollars to Yamaha to clean them!

I'm going to call the dealer and tell him what i'm seeing and demand my money back. I paid with my debit card and I'm going to put a claim on the charge as well!