#1 & 4 pistons not hitting TDC simultaneously???

Our welding price is only for welding. We have long ground rods that we insert thru all of the wrist pin holes to see if it is twisted. If the rod will go thru all four, then we weld it. If not, we send the customer to Gardner. He is the best with the roller bearing cranks.

Try 207-664-0377 or 866-664-0401

Jay

Post edited by: APE Jay, at: 2006/02/25 16:33

@Jeff.Saunders
absolutely correct,many J-motors had these problems.
In Germany we have no speed limits on (many) highways
and in the 80`s our Kawasaki dealers had one of these (high RPM killed) motors every month.
Don't drive with this crank otherwise you will need a new cyl. head,pistons ...

I believe any crank that is pressed together will "twist" under load. Here is a thought what if #4 is the one that IS correct??? I would get it indexed then welded. Sorry to here the situation. Thing do disappear when you move Good luck man.

Maverick:

Good advice here, but I'm curious on what prompted you to disassemble your motor in the first place? Was this a general rebuild, were you having trouble with the motor, was this a recently acquired bike that you didn't know history of? Was the bike running before the teardown? Thanks.

I had a machinst friend acquire a 17mm blank drill bit rod which is VERY VERY precise. I use it as APE Jay describes. Before rebuilding ANY engine, I insert the rod THROUGH the piston pin holes in the connecting rods. The rod CAN NOT go through if the crank isn't true as the rod fits as tightly as the piston pins themselves. It is a cheap and very effective way to check if a crank is straight. If I owned this J engine in question where the crank is definitely twisted, I would NOT run the engine as is and would split the cases and pitch this crank and buy another from eBay OR get this one fixed. I suspect that an eBay crank would be cheaper. If these cranks have a tendency to twist, I would consider sending it to a company like APE to weld. Truing the crank will be fairly expensive but that is, of course, a very viable option as you may not be able to find a crank readily on eBay and may not be willing to wait for one to come up on auction.

If anyone is wondering where to get the drill rod, it's available at MSC for ~$17 plus shipping. Order a catalog while you are there, it's hardbound, huge, weighs 7-10 pounds (seems like it anyway), they ship it UPS, and it's free :laugh: :laugh:

Hi Michael,

Interesting you should ask. I had a red-line 'incident' on my first ride on the bike just before Thanksgiving '05. The throttle stuck open on me. In my panic, I clutched before I hit the kill switch resulting in severe red-line. It never ran the same since. So I tested my compression. All cylinders were low, but #1 was nearly 25% lower than the others. Ran a wet compression test and resulting pressures went way up - nearly doubling on #1. So diagnosed bad rings. Ran a leak-down compression test on the other cylinders which indicated leaking valves. So I tore the top-end off, lapped the valves, installed new rings, and was in the process of buttoning things back up when I noticed the twist.

So to answer your question, it was a new bike to me, didn't know the history (not even mileage b/c the speedometer/odometer was missing), plus had performance issues after the red-line incident. From what I understand, high revs are usually what causes the crank to twist.

So the real question is: "Why in the world did Kawasaki put a press-fit part in such a high torque application?"

Maverick...

Ask anyone who ever owned a 1982 GS1100 and missed a shift when running hard... the answer back them used to be a joke which was to send all the Falicon kids to college bwhahahaha

This isn't unusual for an early 80s bike. I have bent several crank shafts and the reason was missing a shift and running the engine way past redline. There were lots of bikes out there where this never became a problem but the very nature of owning a KZ1000 or GS1100 usually meant that the owner liked to ride hard I guess.. Good luck and keep your eyes on eBay!

1982 gs1100e suzuki it was silver with black yosh pipe spring of 90 broke the crank!was running like a bitch uptill that point!!!!!!!!!!:whistle: :whistle: goodluck,happy wrenching!

steell wrote:

If anyone is wondering where to get the drill rod, it's available at MSC for ~$17 plus shipping. Order a catalog while you are there, it's hardbound, huge, weighs 7-10 pounds (seems like it anyway), they ship it UPS, and it's free :laugh: :laugh:

There you go. You can even check a crank while it is still in the cases.

Jay

Was the issue with Suzuki Gs's the helical cut gear off the crank? Did this not go away after the factory switched to a straight cut gear? At least with a pressed together crank there is the possibility of getting it repaired and trued.

No... The helical gear would cause the clutch gear to get pulled in and hit the crank cheek.. They will still twist with a straight gear if the crank is not welded.

This is why we put the heavy duty backing plates on the Zuk basket assembly to make it stiff enough that it resist being pulled into the crank cheek.


Jay