Running great - if only my plug color wasn't freaking me out

Jlovvorn · Post by **Jlovvorn** » Sat Mar 17, 2012 4:09 pm

Thx. Praying for a stuck slide.
If not, I fear I am done.

rzgkane · Post by **rzgkane** » Sat Mar 17, 2012 11:13 pm

Jlovvorn wrote:Ed has spent hours trying to help me.

Ed has spent a lot of time on the phone with me as well. What a generous guy. Thanks, Ed. Bike ran like a champ after I finally got it together.

I am one bolt away from done for a while. Seems some knucklehead thought the bolt that mounts the right muffler to the engine case needed a standard thread bolt shoved in the hole.

hillhudson · Post by **hillhudson** » Sat Mar 17, 2012 11:34 pm

I have had the racing idle problem with a cb160 and a cb77, its ended up being mainly because of how the throttle cable was threaded through the bike, there is a thread here about proper throttle cable placement.

also make sure you have the correct slide in the correct carb, they have R and L stamped on them, for right and left.

good luck

i feel your pain,

Jlovvorn · Post by **Jlovvorn** » Sun Mar 18, 2012 8:39 am

Since it ran great for 30 mins after tune up, and then went crazy on a 15 mile ride home, I expect the problem to be gone today, and return again on a longer ride.

It seems like it has to be a slide. There is nothing else left, unless the advancer has gone crazy.

Assuming the slide is sticking, is it ok to use fine steel wool on the inside of the carb tube and to shine up the slide valve?

This slide stuck on me before, and I loosened the carb mounting bolts and put just a drop of oil on the slide. I figure the bike got hot and the parts expanded.

I can't go any looser on those mounting bolts without leaking air.

I think the carb or the slide is defective, and want to just dump it and start over.

I found a source for a brand new left carb and slide, but it will cost me nearly $500.

Would really like to avoid that.

LOUD MOUSE · Post by **LOUD MOUSE** » Sun Mar 18, 2012 9:05 am

Send me your carbs. ............lm

Jlovvorn wrote:Since it ran great for 30 mins after tune up, and then went crazy on a 15 mile ride home, I expect the problem to be gone today, and return again on a longer ride.

It seems like it has to be a slide. There is nothing else left, unless the advancer has gone crazy.

Assuming the slide is sticking, is it ok to use fine steel wool on the inside of the carb tube and to shine up the slide valve?

This slide stuck on me before, and I loosened the carb mounting bolts and put just a drop of oil on the slide. I figure the bike got hot and the parts expanded.

I can't go any looser on those mounting bolts without leaking air.

I think the carb or the slide is defective, and want to just dump it and start over.

I found a source for a brand new left carb and slide, but it will cost me nearly $500.

Would really like to avoid that.

Jlovvorn · Post by **Jlovvorn** » Sun Mar 18, 2012 6:27 pm

Wow, that's very generous. I will need to pay you for your time on them. Will send you PM.

Update for today - more craziness:

Started over at the beginning.

Took carbs off. Blew through all the holes, redid float levels several times. Replaced o rings on flanges, and gaskets up on the throttle cap.

Changed needles to match - one looked different. Second setting from the bottom. Changed jets to 140s. Checked slow jets, they are clean.

Set the mix screws at 1 and 1/4, checked both slides raising at exactly the same time. Both bottom out with play. Slides are not hanging up.

Reinstalled carbs, and again, the engine races up and down. When it stops racing, it drops down and stalls, unless you set the idle way up.

Did the timing - again. It seems like the plate shifted after yesterday. Reset it and marked it with a sharpie so I can see if it moves.

This improved the situation - no more big racing, but idle still goes up and down.

By fiddling with it, you can get it so the high idle is about 2200, and the low about 1100, and it seems to stay between those extremes.

This is on stock airboxes, and stock exhaust.

I am feeling that this is not a carb issue.

I think its a timing / advance issue, and something is really wrong somewhere.

I have some video of it running, but since it never does the same thing twice, not sure how useful they are.

Jlovvorn · Post by **Jlovvorn** » Mon Mar 19, 2012 7:13 pm

More entertainment tonight.

After a long talk with LM, went in and reset my throttle slides without the idle screws in, and behold - the left carb was lifting way later than the right.

Somehow they seemed in synch with the idle screws in, but out told the real story.

But the fun didn't end there.

In order to get left and right to raise at the same time, I had to screw the left top screw almost all the way out, and the right one all the way in to get them even.

Why would my cable be so far off on one side than the other?

Got them to even, kicked the bike over and it raced up to 5000, and I had to kill it.

Seems like the throttle slides are not bottoming out.

So I take the needle up from second to bottom to middle and it still races, just not as bad.

I am thinking maybe my cable is too short?

I am going to post a picture of what I thought was bottom.

Right now, there is about a 1/2 inch gap of the cutout visible when you look down the throat with the throttle closed.