Engine Rev while riding after bike is warm

[Nani]

Help!
I have a 1993 GL1500SE. After getting my bike out of storage, my husband noticed that there was no fluid in the clutch reservoir. He saw no leaks anywhere. He refilled, but said the clutch still felt a bit spongy. He rebuilt the master and slave clutch cylinders, bled the air, etc. I took it out for my first ride of the season last Saturday. The first 100 or so miles was great. Then, pulling out of a fas station, the front end seemed to "shudder" momentarily and then was fine. Then after a stop sign, the engine would rev, but excelerated very slowly. Did this in 2, 3 and 4, but was fine in OD. Husband looked everything over again and no leaks, etc. A suggestion was made to clamp the clutch handle for a couple of days to get out any air. Did this and all was fine again. Started to ride again today. Everything was fine for the first 30 milesor so, but after a scheduled stop of 15 minutes or so, I started fine, but then the engine started revving again while at cruising speed. With or without cruise didn't make a difference. It got increasingly worse so I decided to turn back toward home. I couldn't go any faster than 50MPH and had to SLOWLY get it up to that speed after MUCH gear slipping. By the time I got back to town, I couldn't get above 15-20MPH. If the bike is in neutral, it's fine, but in gear, with clutch handle in, it makes a grinding sort of noise, which slows when put in neutral.

Sorry if this isn't making much sense but I'm a rider, not a mechanic. My husbandxand I gavexa weekend ride planned for next weekend and I'd rather not do it on my Shadow 700 if possible. Can anyone give me any idea as to what the problem might be and how to fix it? Thanks!

[MikeB]

You said...

He rebuilt the master and slave clutch cylinders, bled the air, etc.

But you did not say if the oil was drained and refilled and what oil was used. Was the engine flushed of any brake fluid that may have gotten into the crankcase?

[Nani]

Honda oil and filter were done last week as well. No problem with brakes.

[MikeB]

Honda oil and filter were done last week as well. No problem with brakes.

I didn't say there was anything wrong with the brakes. DOT4 Brake fluid is used in the clutch system. Brake food will leak through the clutch cylinder into the engine and cause bearing failure.

[Nani]

Ok. Thanks. Is this something that would happen immediately? Worse when the engine is warmed up? DOT 4 was used. I don't know if he flushed the engine or not. Can you tell me what bearings would be involved? Thanks again for all your help.

[MikeB]

I can't say with 100% certainty but I'd say every bearing in the engine that is lubricated with engine oil is in jeopardy.

I also do not know how quickly they would be affected.

[Rambozo]

Sounds like the return hole in the master cylinder might be a bit plugged. It's a very small hole and usually has to be cleaned out with a wire.

[Nani]

Is this something that gets worse as the bike warms up? At the start of last week's ride, it was only 34 degrees outside and fairly windy so the engine stayed cooler longer I'm guessing. Yesterday it was already 80 degrees out when we started. I know the engine hets hot regardless, but wondering if air temperature would have any effect, or if it's just gotten more plugged over time.

[MikeB]

Sorry if this isn't making much sense but I'm a rider, not a mechanic. My husbandxand I gavexa weekend ride planned for next weekend and I'd rather not do it on my Shadow 700 if possible. Can anyone give me any idea as to what the problem might be and how to fix it? Thanks!

It would be beneficial if you had a mechanic that could inspect and evaluate your issue.

[LaclaMoe]

My guess. Leaked in storage, then ate your clutch. Then started falling apart when you used it. It’s slipping when you rev it.
With an oil change I doubt the small amount would do in your bearings.

[Nani]

Do you think replacing the slave cylinder would fix it, or do I need a whole new clutch?

[WingsandThings]

It might help if you could tell us the exact type of oil you used when the oil was changed.

[Nani]

Honda oil and filter. Also note that this happens whether I'm trying to shift gears, or just cruising. I was in OD and using cruise and it was still doing it. Like it was just "popping in and out of gear." A new clutch isn't cheap, so I hope that's not it.

[WingsandThings]

Have you used that exact oil before?
Some oils are "energy saving" and can possibly cause problems with clutch slippage.

[LaclaMoe]

Your saying as you drive it’s overrevving. That’s clutch slip. There’s a slim possibility something is holding clutch open(slave etc) try bleeding, is there a lot of pressure at rest? Rule that out and I’d say time to open it. Best option, make hubby ride the 700 until it’s fixed.

[Nani]

Thanks. Everything was bled. Not sure what you mean by "pressure at rest." Hubby would ride the 700, but we just got his Goldwing last month and I want him to enjoy the ride too. Our weekend rally is only 2 1/2 hours away, so not a big deal on the Shadow.

[LaclaMoe]

I meant make sure the master is releasing the pressure. If it’s not, that would keep fluid pushing the slave to open your clutch. But that wouldn’t explain the jerking. So i lean towards clutch material expanding, falling apart.
Hope I’m wrong. It’s not that expensive