Topic: Possible Clutch Slipping Issue

[acb]

Recently had my engine rebuilt by HondaMan and have been taking it really easy (keeping it under 3000rpm) for the first 500mi or so to break everything in.   

I finally got it out, and above 3000rpm last weekend and it seemed to be doing great until I hit 65mph (in 5th gear) as it was coming up on 5000rpm and it just quit on me – oil light came on (just as it does whenever I finish a ride and hit the kill switch) and I coasted to a stop.

I had been riding a good bit beforehand and just before it happened I noticed the oil pressure seemed low but was coming up when the  RPMs went up – just not to where it normally does.  Also, I had just done an oil change (10W40) before the ride.

After I came to a stop I did a visual inspection and everything looked fine, I shifted back down into neutral and it started right up again.  Took it easy for the rest of the ride and it seemed fine. After a short break, I did notice a faint clicking/tapping sound that mimicked the engine/exhaust sound when I gave it throttle but it didn't seem concerning or causing issues.

My first guess is this might be the clutch slipping but I did some searching on the forum and it was hard to determine if it was similar problem to other clutch issues. I also thought I might need to be using a heavier weight oil – when I checked the oil out it seemed really thin.

I am concerned though – Is this the clutch slipping? Or something different? As always any help is much appreciated!

[bjbuchanan]

You are doing the total opposite of breaking the engine in... You have to use more of the rpm range, I would be amazed if your rings seated nicely.

It sounds like electrical to me, the engines rarely just shut off totally when you are moving in gear. The rolling momentum usually keeps them alive until you pull the clutch in

[acb]

You are doing the total opposite of breaking the engine in... You have to use more of the rpm range, I would be amazed if your rings seated nicely.

It sounds like electrical to me, the engines rarely just shut off totally when you are moving in gear. The rolling momentum usually keeps them alive until you pull the clutch in

Interesting about the "breaking in" – HondaMan had told me to keep it under 3000rpm for the first 500mi or so to break in the cam chain specifically. So was just keeping to his advice.

As far as electrical, that was my first thought as well, but when I looked at the indicators and saw that the oil light was on (I believe my signals were working as well), I assumed my electrical was still doing ok. That's not to say, that it's something specific with the engine electrical though.

[bjbuchanan]

Different strokes for different folks. I respect his opinion but I still take more modern approach to break in.
The odd thing is that it started right up right? Or did it not?

[acb]

The odd thing is that it started right up right? Or did it not?

Yes, started right up again.  Like nothing happened.

[MiGhost]

To start off with the oil. In the warmer weather it is not a problem to run a heavier oil. 15w40, or 20w50 will be good as long as it is a motorcycle rated oil. Most of the common car rated oils have friction modifiers that could cause problems with wet clutches.

A clutch slipping would be identified by the motor suddenly spinning up faster than the speed increase. It is very noticeable.

As the motor was just reinstalled. Have you rechecked the exhaust to make sure it is still tight? 

[acb]

To start off with the oil. In the warmer weather it is not a problem to run a heavier oil. 15w40, or 20w50 will be good as long as it is a motorcycle rated oil. Most of the common car rated oils have friction modifiers that could cause problems with wet clutches.

A clutch slipping would be identified by the motor suddenly spinning up faster than the speed increase. It is very noticeable.

As the motor was just reinstalled. Have you rechecked the exhaust to make sure it is still tight?

Good tip on the oil – I think regardless of what happened, probably good to go with a heavier oil until it cools down a bit.

Thanks for explaining what a clutch slip would be/sound like.  I was unsure, and I'm fairly certain now that whatever happened was not that.  Speed increase and motor seemed to be in sync, motor just suddenly quit.

I rechecked the exhaust, once, early on, to make sure it was tight, but probably good to do it again now as well.  Fairly new to working on my bike so apologies if these seems like an obvious question but how could a loose exhaust cause something like this?

[MiGhost]

I rechecked the exhaust, once, early on, to make sure it was tight, but probably good to do it again now as well.  Fairly new to working on my bike so apologies if these seems like an obvious question but how could a loose exhaust cause something like this?

As the bike gets run through the first few heat cycles. The exhaust gaskets get heated, and cooled to make a seal. If the pipes do not stay tight against the gaskets they shrink away from the pipes and cause leakage. This will sound like the tapping that you describe.

[excellrec]

When it quit did you pull in the clutch?  If the motor stopped running and the rear tire wasn't spinning the motor then the oil light should have come on because the oil pump was no longer spinning either.  Also, the oil pressure should lower when the bike gets warmer.  Whenever there is an abrupt stop it usually indicates an electrical problem, as fuel delivery problems are usually preceded by a choking or bogging before the bike stops running.  I would be looking for an electrical issue here.

[acb]

When it quit did you pull in the clutch?

Honestly I don't remember if I pulled in the clutch or not – I was so surprised the engine quit, all I remember is seeing the oil light on.  My guess is that I did not pull in the clutch, at least not before I coasted a good bit.

Interesting about electrical though – any ideas as to where I might start looking for engine electrical issues?

[Stev-o]

Have you spoken with HM? Im sure he would help you figure this out.

[acb]

Have you spoken with HM? Im sure he would help you figure this out.

Not yet, hoping to soon though. 

[acb]

Was just doing another search on the forum for electrical issues/engine shut down when riding and found these:

http://forums.sohc4.net/index.php?topic=123788.0
http://forums.sohc4.net/index.php?topic=57904.0

Could be the ignition – I have had some trouble there in the past. It was day time when I was riding so hard to tell if the entire electrical went out for a split second (gauges/headlight went dim etc) but it's definitely a possibility.  I'll try to investigate and post what I find.

Thanks everyone for the help!

[PeWe]

Breaking in...
I did it this way.....That is a prooven way to do it. A guy here in Sweden wrote his thesis on a technical institute that confirmed it by practical tests. http://www.mototuneusa.com/break_in_secrets.htm

From the very beginning, idle to warm on 2000rpm to ensure oil pressure. Then drive it and twist the throttle really hard, at least 6000rpm and release so you get hard deceleration. Do this several times It's now the rings will grind them self and seal. The honed bores will do this the first miles only. Perfect in city, between redlights