TOPIC:

I have a small problem with my 85 KZ-P. I picked this bike up for a song and though it had more that $2300 spent on her prior to my ownership, I have been updating and replacing things for its new life as a funeral escort bike.
I bought new front and rear sprockets (35 tooth rear) and new chain. The rear was simple, but I can't get the front off. It seemed to be in good shape, but I wanted to replace everything at the same time. There is no multi tooth lock washer/nut, only a flat washer that was turned up to lock the nut in place.

I assume that the nut is lefty loose like everything else. Air hammer, breaker bar, breaker bar w/cheater, old chain wedged with screwdriver, new chain with brake on and tranny in first, propane torch to heat up the nut, NOTHING WORKS. So far it hasn't budged and I have only cursing and a broken sprocket tooth to show for it.

What can I do to get this thing off? Is it righty loose?

Please offer workable solutions. Every day the bike sits idle is less money in my wallet.

if you can get the chain installed and bike sitting on its own feet you could take a breaker bar and a 10' piece of 1-1/2" to use as a cheater pipe while somebody holds the brakes.
make sure that washer is flattened out first ,ive done it that way before without breaking things

get a cutting disc for ur grinder, CAREFULLY cut a section or two off, then vise grips or something else will get it, dont cut the threads on the shaft, worked for me

I have tried the breaker bar, but haven't tried it with the bike on the ground, just on the stand. My next try will be with a much longer bar. If it doesn't budge then, I guess the grinder is coming out.

The washer is flat and I have tried it with and without the chain on, and with and without the brakes and chain on.

Thanks for the help guys

As mentioned, the bike must have a chain on it and rear wheel secure or sitting on the ground. Than be persistent with an impact wrench.

May need a more powerful air hammer (impact wrench).

Here's one method for holding the sprocket in position:


As already mentioned, must be careful not to damage the spline draft shaft.
Would not allow grinder wheel to touch the spline drive shaft.
Enough surgery on the nut should allow final removal with a chisel, all without ever touching the splines.



If must resort to grinding, instead of the larger grinder pictured above, would elect to use Dremmel tool (likely consume several cutting wheels) and proceed very slowly. Being smaller and less aggressive, the Dremmel tool is imo more precise and easier to control

Wear eye protection.

Good Fortune!

I wonder if some knothead put red Loctite on it when they put the nut on? Might try a little torch heat on it, I would definitely apply penetrating oil on the nut. Holding the rear brake and twistinf usually works, not sure why yours is such a bear to get off.

I agree that someone could have put on a thread locking compound. I would carefully heat up the nut (nut only as best as you can) and then put the impact wrench on it. Set it at 110+PSI and the highest impact setting. Make sure that the sprocket is locked down with a chain. Do not attempt to hold it with the transmission.

I used a 1/2" break-over bar that is about 16" long. You may use a pipe as a cheater, just be careful. I found it helpful to place a cinder block plus some wood under the head of the bar where it turns 90 degrees to fasten to the socket or the extension. Then stand on the far end of the bar. Best to have a small stool nearby to step onto when the nut comes loose. Otherwise you can really take a fall to the ground. Watch those shins also. Wonder how do I know this? Good luck.

You get a lot more bang for your buck with "shock" on a frozen nut than simple torque twist. An impact wrench or even a large box end wrench with a hammer banging on the handle sometimes will shock the nut loose better than twisting it.

If you have not tried it, apply acetone spray (carb cleaner) to the threads and then apply a penetrant like Kroil and let it sit overnight.

If that fails, I think heat followed by impact wrench is the best shot.

Put the old chain back on and have an assistant hold the rear wheel brake dead tight while you beat on the nut. I wouldn't want to put that much stretch force on the new chain just because it might stretch it.

Have you tried PB Blaster yet?

Success!!!

I used a 5 foot long jack handle and supported everything with a jack stand. I really thought that I was about to shatter the socket but it held.

Thanks everyone for their ideas and comments.

$2300 (parts and labor to a local shop for resealing and new gaskets, etc back in 2007)
I paid $500 for the bike two months ago

New: brake pads, tires, fairing pockets and covers, battery, stator, rectifier, chain, front and rear sprockets, custom oil cooler,coils and 8mm suppression wires, JM Audio CB, misc parts

Coming: rebuilt carbs from oldskoolcarbs, should be ready in two weeks

Needs: rebuilt or replacement speedo and tach. The speedo needle snapped off. It has read 10-25 mph low from the get go. The tach is jumping everywhere. Don't know if it's a bad connection in the 26 year old wiring or it just got old. Might fix itself with the new coils. I'll find out tomorrow afternoon when I get everything bolted back together

I'll have $2700 in it after the carbs arrive. That includes a new helmet and the CB