Squealing squeaks

[rockdr]

The new guy here. Bikes all my life mostly HDs. But have fallen for the xs. Pulled one from a bone yard 1977 with 20k on the speedo. just cranked it and has a loud squealing noise that shifts with rpm. No breathers and wont run with them so I am sure not an air leak (carbs have been cleaned).Doesnt want to take the throttle especially on the left bank and doesnt want to make power going down the road. Compression feels good on kicker. Alot of vibration on higher rpm. The wierd thing. Listen to the cases with stethascope and she sounds great. No squeal nothing. . Wish my HDs sound that good. wondering if run with no oil before and burnt the bearings. Any ideas.

Seems I have heard this noise before on another bike(77) I looked at but not as loud.

Rock Dr

 

[Classic]

Check your cam chain guide and adjust it if need be and replace or gap the points and set the timing.

 

[rockdr]

Will Do.

 

[rockdr]

OK guys, checked time chain. adjusted about 1/16 inch. Set points and Then checked timing. Re checked and checked again! It is firing with the point break exactly when the rotor mark is on the last stator line "A" in clymers ie TDC and way late. So we rotate the breaker plate till we fire between first 2 lines or F in clymers. this will be tomorrows operation and we will try another test run.

Check me on this now, top point, marked R, grey wire is right hand cylinder. Right Cylinder is firing when compression is built on upstroke on right side while on the left no compression is built on the same upstroke. Correct?

Thanks,
Rock DR

 

[XSLeo]

Correct. When one cylinder is coming up on compression the other is coming up on exhaust. They fire 360 degrees apart.
On the Harley the when the front fires the rear fires 315 degrees later, if you look at it the other way the rear fires then the front fires 405 degrees later.

 

[rockdr]

WELL world of difference with proper timing. timed right up. I guess that is an indicator of time chain wear. (20K on it). good power now. BUT It squeaks like hell! Bird chirping sounds loudest on left but hear it on both.open breathers so not intake leak i am sure. might be coming right out the pipe.wish I had a shorty muff to put on it. See if it quiets it. and a distinct constant popping in and spitting out of left carb, and pop in the pipe too it think. Right side is great. Idles great,. Replaced left plug no diff. Exhaust is open factory header, not ideal but will have to do for now.

Going to service the oil filter, put old plug in left side and burn some mavel oil through it. Have done a little on both sides before. Somebody must know what I am talking about with this chirping. It is LOUD!

still having fun!

 

[pumps]

I'm not sure but if it seems to come from the carb? I want to say butterfly throttle shaft seal? Maybe this is it?
http://www.xs650.com/forum/showthread.php?t=1873&highlight=chirping

Did I mentioned you HAVE to put up some pictures? LOL

 

[retiredgentleman]

I agree with pumps. You likely have a air leak.

On my 78SE, the chirping started a few years ago. I replaced the carb throttle shaft seals and the chirping stopped. However, at about the same time, I replaced the stock carb intake manifolds with ones from Mikesxs. That was a mistake!

The chirping returned, and I finally found it sucking air on the right intake manifold. Replaced the (almost new)Mikexs manifolds with my 32 year old stock manifolds and chirping is gone.

With some careful measurements, I found that the ones from Mikesxs are not correctly sized and are a lose fit. The OEM manifolds are an interference fit and fit tightly with the carbs.................which means no air leakage.

 

[shaas]

Aren't the stock exhaust head pipes double wall? If so it may be that they have separated. I had this happen to another bike I owned and it squeaked loudly. I convinced my ex that it needed a cam and header to cure it. The pipe on that model was notorious for failing. (Honda Ascot)

 

[rockdr]

good call on the pipes.We'll check it in detail.give the carbs a 100% clean as well. That pipe thing is making sense though. thanks guys.

 

[weekendrider]

A 77 with points. The advance rod could be the source?

 

[gggGary]

Aren't the stock exhaust head pipes double wall? If so it may be that they have separated. I had this happen to another bike I owned and it squeaked loudly. I convinced my ex that it needed a cam and header to cure it. The pipe on that model was notorious for failing. (Honda Ascot)

Had an FT500 it had the failed pipe, drilled a hole and welded it problem cured but I won't tell your wife! Yes the stock pipes are double wall.

 

[XSLeo]

Try squirting some wd40 or carb cleaner around carb holder, at head and carb. Around the throttle shafts too.