Kat nap

[Carter Turk]

Did two trackdays in June. Last one 2 days ago. Managed 54 laps on Monday, doing Lemans starts, due to the starter clutch giving me the business right when I was loading the bike into the truck. It started once, then I parked it to let the engine heat soak for a moment while I set up the ramp on the truck. Hit the starter button again and all I heard was spinning, spinning nothing. Great... trackday paid, ferry reserved, friends to meet at the track. Does this mean I shouldn't go? Maybe some sign from the spirit world? I already loaded most of the other track neccesities, so I ran down the street, bumped started in second, lined the bike up on the ramp and walked it up in first gear. No issues there, but my legs were shaking in the bed of the truck while cinching the tiedowns, probably from all the youtube loading fails.

A lot of maintenance and new parts were purchased, before my first day on the track this season: New tires F/R, chain/sprockets, battery, oil/filter, used HD clutch basket, clutch springs, throttle cable, fork oil, used leather suit. Valves adjusted, carbs synched, float height checked, new oil, regreased tapered roller bearing in steering stem, fork oil, oil/filter etc.

The day went well, it was hot and dry, no red flags, in our group, no sessions stopped out of 8 20 minutes a piece.

Tonight I investigate the starter clutch, it spins both ways, but the 12-9 bolt threads are still in the rotor. I pull the rotor, and starter clutch out, then I notice the large thing in the left of the picture underneath the starter gear. Remove the exhaust, drain oil, pull filter, remove oil pan and sump screen and find all this... Most of it cylinder sleeve, with a few chunks of aluminum and possibly a piece of transmission bearing retaining plate. No sign of the heads of three starter clutch bolts. The crazy thing is the bike ran great despite all this carnage. Guess it's time to put her down for awhile.

[2BRacing]

This is proof that a Kat has 9 lives!

[Gregory]

Since I haven't encountered that before, when I saw that picture I had a sinking feeling... kind of like that picture should be in the dictionary for the word SAD.

But my experience here on this forum has proven to be invaluable in turning the overwhelming into the "easily fixed" category.

I know I haven't added anything to the conversation, but am going to follow this to learn about this situation.

I am hopeful that it is a lot spookier looking than it really is.

[Big T]

Wow Carter

looks like a complete tear down is in order

[BigD_83]

Damn...that is a major bullet dodged. Good thing one of those bits of shrapnel didn't get somewhere critical in the middle of a 100mph sweeper.

Unfortunately, a teardown is on the near horizon...or is this now a winter project? At least you have the ES to ride, if your wife will let you.

[Carter Turk]

Wow Carter

looks like a complete tear down is in order

Not looking forward to it honestly. Just had the cases split last summer for the Pearson undercut tranny. Haven't looked at the pistons in 13 years. No idea where the bolt heads went for the SC unless they twirled around into metal shavings. I also stole my ES motor for the track when I was waiting for tranny parts on my bike last summer. Actually it was a bearing mix up on the input shaft. So this will be the third motor I've pulled in less than a year.

I need a 1229 block, if my pistons are still there. I have a spare stock block.

BigD, yeah I was worried about that too. All that stuff except the sleeve piece on the ruler was resting on the oil pan cover or in the sump screen.

Just for the record, I don't think the thrashing on the track had anything to do with this incident, I almost wonder if the idle gear is incorrect or 1100 spec, because I've been dealing with starter clutch snatching for years. This is the 6th one. I looked at the idle gear, there's no marking whatsoever, to identify what it is. I guess I have to count teeth?

[Guest]

Hi, if the rotor has ever been lapped on the crank, the gear pinches the copper washer and it all tightens up. Then the gear starts to turn all the time.
Think about, but the whole engine needs to come apart and I think the #1 cylinder sleeve will be all broken. Maybe the cases will be banged up inside as well. 1100 and 1150 starter gears are the same if big tapers but the idler gear has a different pitch for the starter which is different on the 1150. Interesting as to how the hardened steel pin was not broken or sheared off when the bolts broke.
Hope it works out. Maybe get a whole, spare engine as well?
Laters
G

[Carter Turk]

Hi, if the rotor has ever been lapped on the crank, the gear pinches the copper washer and it all tightens up. Then the gear starts to turn all the time.
Think about, but the whole engine needs to come apart and I think the #1 cylinder sleeve will be all broken. Maybe the cases will be banged up inside as well. 1100 and 1150 starter gears are the same if big tapers but the idler gear has a different pitch for the starter which is different on the 1150. Interesting as to how the hardened steel pin was not broken or sheared off when the bolts broke.
Hope it works out. Maybe get a whole, spare engine as well?
Laters
G

It's a big taper, this rotor is fairly new, not new per se, but a different one, maybe the third one since getting it on the road. Last one had to be destroyed to remove, due too much red loctite on the taper. My fault. The previous spun loose and was rubbing on the wiring bar holding the stator wires. Also the original dowel on the back of the rotor dropped out of place, so I had machine shop turn a longer one, but that bashed its hole making it oval. This last one, I didn't bother, because the three bolts broke anyway with the pin in place.

[rapidray]

I REALLY wish you guys would listen & just weld up the starter clutches like I have suggested over & over. They stop breaking the 3 bolts once you weld them & these kinds of problems pretty much stop.
Ray.

[Guest]

Exactly what Ray said... I broke every kind of hardness bolt I could find and then brought it to my favorite welder. If anyone needs a pic of where the welds should be, I will take it apart and get it published...
Curt

[Carter Turk]

I REALLY wish you guys would listen & just weld up the starter clutches like I have suggested over & over. They stop breaking the 3 bolts once you weld them & these kinds of problems pretty much stop.
Ray.

Ray, don't recall me not listening, but sounds like this is necessary next time.

My next quandary is what to do with the damaged block? Should I resleeve the damaged one (or two) sleeves and have it bored or have a stock block bored to fit the MTC pistons I have in there? A streetable head gasket and base gasket will need to be purchased too. The motor has been oil tight with regard to the gaskets, even without heavy duty APE Bolts.

Gmansyz, looks like a lot of pressure was on the copper washer, but as far as I know the rotor wasn't lapped.

Bellucci, would like to see where the welds need to be, but don't want your motor torn down just for a picture.