Broken lifter

[Katana quad]

I just picked up an 89 750 for a good deal. It had dark coloring in the intake runner of #2 cylinder and the carb had some melted pieces. I pulled off the rocker cover and it's exhaust rocker was snapped in half. Not opening the exhaust valve causes the bike to use to carb as the exhaust system. Probably not the fuel mileage you would hope for. It's amazing the thing didn't burn to the ground. Anyway I have access to a set of rocker arms from a 600 and was wondering if anyone knows if they will fit. They look the same but I checked part numbers on Bikebandit and they are not the same (1043535 to 1043531) I know that should be the end but I'm stubborn and was wondering if anyone has tried it.

[arsenic]

So you've proven that it's a different part, but you're asking if it's the same?

[Katana quad]

I was just wondering how it's different. It could be a desired difference like opening the valves a couple extra thousandths. If anyone has used them and they work I would be willing to try.

[92xjunker]

88-89 are different from to others, engine wise, ? You have 2 options buy it and match it up or buy the correct one. Fyi- you need to have the valve trane balanced, the possibility of other issues related to the rocker failure is very possible, like blown head gasket, bent valve.....

[arsenic]

The 600 is actually all kinds of weird at all kinds of random intervals. The 88-91 600 is tappet screw valve adjustments. The 92-97 a tappet shims. The 98-06 is screws. The spark plug diameter is different 88-95 and 96-06. It really makes very little logical sense. As far as the part the OP needs, Spend the money and buy the right part. If you try to dick around piecing stuff together, you end up getting nickle and dime to death.

[92xjunker]

It's the KR way

[arsenic]

It's the KR way

I'm aware of the dumbassness that occurs here. Along with massive cheapassness. Which often leads to dumbassness.

[92xjunker]

Or visa versa

[Katana quad]

Got it. I'll just buy new. Thanks didn't even think to check the valves. Hopefully there's no other damage. I guess I'll do some more disassembly before I order parts. I wonder what this bike went through with the PO.

[shpielers]

I wonder what this bike went through with the PO.

Assume hell and go from there.

Really, assume the worst. As in 0 maintenance done, and it was down at least once. If you buy a used bike, you should basically do everything possible to it maintenance wise - the PO might have done it...but unless you have documentation to back it up, just assume they didn't. You'll probably be right.
As far as assuming it went down, that leads you to check the bike out more thoroughly looking for damage/Fd up/halfassed repair jobs. Better to discover these types of things early on and correct them than have the bike leave you stranded somewhere miles from home later on down the road.

[Purplehaze]

Assume hell and go from there.

just assume they didn't. You'll probably be right.

Words to live by.

[Kreylyn]

Agreed. If you have a broken lifter, I would consider the possibilities of the cause for such damage. I'd suggest you have the head removed and inspect the piston/cylinder, valves, and such to make sure the damage was not from a physical over rev that forced a piston into a valve.


Krey

[Xrayron]

I'm aware of the dumbassness that occurs here. Along with massive cheapassness. Which often leads to dumbassness.

CraftAssness... often leads to feelings of RepaiRemorseness

[Katana quad]

Ok. So after disassembling the head, I ended up putting in all 4 exhaust lifters, a exhaust cam, one of the lifter shafts and the new cam bearing caps. The pistons, valves, and intake side stuff all checked out good. As was the timing chain, idler, and tensioner. Motor is all back together and I'm just waiting on more carb parts to come in so I can hear this kitten purr. The old exhaust cam looks like somebody took a grinder to it and made some flat spots. I guess the lifter didn't like the uneven terrain and decided to break in half. Thankfully all the pieces stayed in the recesses in the head.

[92xjunker]

The most motorcycles don't have lifters, rocker arm would work or cam follower.