TOPIC:

On my 1982 KZ650, I replaced the 652 cc cylinders and pistons with 738 cc from another engine. The bike has so much more power and compression. After 37,000 miles I had to replace the brushes in my starter. They were worn completely away.

Now the bike cranks over well and fires up immediately. The odd thing is that sometimes the starter makes this "wheezing" sound as it winds down. Everything functions very well, but I wonder if there might be other repairs on the horizon due to this sound. Anybody experience this? Thanks.

Did you grease the bushings? Also the starter clutch could be going out.
Steve

Yes, I did grease the bushings quite well. You are probably correct about the starter clutch. If I understand how it works, the engine spins the clutch upon starting, and this disengages it from the flywheel, but would also explain the "wheezing" sound. I will live with it for a while, and post up when I discover what it is. Just hate to tear into something that is working so well.

The starters the are chain drive have a habit of making that noise before they fail.
Steve

WABBMW wrote: On my 1982 KZ650, I replaced the 652 cc cylinders and pistons with 738 cc from another engine. The bike has so much more power and compression. After 37,000 miles I had to replace the brushes in my starter. They were worn completely away.
.

Sounds like the added load from high comp is causing the starter to draw a lot more current than it's designed for. Probably hard on batteries and starters.

Slipping starter clutch makes an awful screeching noise, starts occasionally on the compression 'bump' but then gets worse.
The sound is quite unmistakeable, not really wheezing more screaming.

The starters the are chain drive have a habit of making that noise before they fail.

(On the 400-750cc air cooled fours the starter turns the primary shaft to crank via the primary chain. 900-1100 series the starter clutch is direct on the crank )

The chain slack whipping contributes to the starter clutch making noise.
Steve