KZ305 Rebuild...attempt

wrote:

Try heat cycles. Also strike the head of the bolt with a brass bar and hammer. Hit it like you’d strike a bell. Quick firm, but not heavy. It will help shock them loose. Do you have an impact driver. Invaluable tool for motorcycle work.
 

Yea I've been tapping them gently a couple of times a day too but I do not have an impact driver. I keep meaning to get one and forgot again today when I was at Horror Fright.

You can also use a center punch. Place the point in the middle of the X [on the screw head] and hit as usual, using a ball pein hammer and eye protection.

Sometimes the focused blow from the punch is enough to jar things loose.

For one of the bolts holding on my clutch cover, I think the upper left, I had to use vise grips clamped pretty stiffly onto the head to get it free, it had slightly fused itself to the dowel pin. The bolt is a little marked but I feel like this bike has two few cylinders for anyone to mind. 

wrote:

For one of the bolts holding on my clutch cover, I think the upper left, I had to use vise grips clamped pretty stiffly onto the head to get it free, it had slightly fused itself to the dowel pin. The bolt is a little marked but I feel like this bike has two few cylinders for anyone to mind. 


 

My clutch cover uses pan head aluminum JIS screws (or maybe stainless...but verrrry soft). But I did get the stripped one loose just now, by cutting a slot and using a large flat head screwdriver. The others are still fused tight, but there is no hurry.

Are you using an impact driver on those side cover screws?  If not, you need one.  

Edit: noticed you are NOT using an impact driver.  This is a big mistake.  Most of the sidecover screws take a #3 bit and a couple good whacks with an impact driver will have them out ready to be reused.  No stripped heads.

BTW, the screws are carbon steel which has been zinc plated.  Don't worry about the JIS business, a standard #3 bit in the impact will have them out pronto.  And use a large heavy hammer if you have one.

yep I plan to grab an impact driver next week, but its a 30 mile drive one way. And I don't have any real JIS anyway, just "stealth JIS" bits and drivers.



 

Order this and save yourself a drive

www.amazon.com/Lisle-29200-Hand-Impact-Tool/dp/B0002NYDRG

Great news - I found a mention with some photos of the blanking plug that causes issues. z250.co.uk/service.html

 

There's a PDF with some good info. I'm not 100% on the location still but with the photos I should be able to find it...and it seems it may be doable without splitting the cases. 

Good luck, intrepid explorer. Take pictures showing its exact location if you find it. There will be no case splitting in my garage...

Anyone know why GPZ305 standard pistons wouldn't work in my bike? They are different part numbers (13027-1052 for the gpz vs 1051 for the KZ) but I don't know why they'd be different. The standard piston I ordered a week ago is now unavailable they say, and that was the only one I could find. 




 

It looks slightly different (angled-to-flat piston top, while the standard is a dome), and the parts numbers for the rings are different, but I'm not sure why they would be different. Same compression ratio, as well as the same piston pin. 

The crankshaft is a different number as well, but looks the same. I'm not sure why the Z305 and GPz305 would be produced at the same time but have different parts - but it's possible. 

And here's one in Malaysia with the right part number but not at all like my piston. 

www.facebook.com/commerce/products/2530631393715598

Oh wait...that must be an oversized but it shouldn't be.  Getting confusing now...

EDIT: My bad. The right part is 13001-1051, not 13027....but they're just as unavailable