kz1000j crank twisted?

Hi there . My name is dean.

I have checked my crank. I turned the crank at half stroke and then mesured the space from top of piston to top of barrels. There is about 1mm diference between 1 and 4. Does this mean the crank is twisted. Does vibrade alot and right through al the revs it is almost forgiving but yes iratating at the foot pegs.

Is there a nother way to determine this before sending crank for truing.


Thanks

Sadly it may be the case. The early J engines were notoriously bad about twisting the crank. The only fix is a different crank, or to get your crank reindexed and welded. Make sure your measurement is accurate before you pull the engine apart. Once you get the piston pins out, inserting a 17mm diameter rod through the connecting rods will show if there is a problem or not.

Jeff.Saunders wrote: Sadly it may be the case. The early J engines were notoriously bad about twisting the crank. The only fix is a different crank, or to get your crank reindexed and welded. Make sure your measurement is accurate before you pull the engine apart. Once you get the piston pins out, inserting a 17mm diameter rod through the connecting rods will show if there is a problem or not.

Hi jef do you think 1mm can make such a vibration.

Have play on the clutch basket as wel.

I wanted to order some stuff from z1 but it is exspensive for send it over. Wil you be able to send some stuff over with normal mail over to south africa?

Thanks for your reply

deanbyron wrote:

Jeff.Saunders wrote: Sadly it may be the case. The early J engines were notoriously bad about twisting the crank. The only fix is a different crank, or to get your crank reindexed and welded. Make sure your measurement is accurate before you pull the engine apart. Once you get the piston pins out, inserting a 17mm diameter rod through the connecting rods will show if there is a problem or not.

Hi jef do you think 1mm can make such a vibration.

Have play on the clutch basket as wel.

I wanted to order some stuff from z1 but it is exspensive for send it over. Wil you be able to send some stuff over with normal mail over to south africa?

Thanks for your reply

YES 1mm will make a vibration for sure I do have a NOS 'J' crank if you are interested.

My 1980 A4 crank was 40 thousandths out of index on the number 4 crank throw during rebuild.

What is 1mm in thousands....must be more than 40 thousandths. I have been told that 40 thousandths is the max you want to be out?

I would agree with Jeff. Need to run numbers and be sure its out before breaking it down. If it is out of index you better address it.

1mm. equals approx. .040"

Hi Dean

Which part of SA are you in? The motor on the bike in my profile pic was built by a guy in Honeydew that I am sure could help you out, maybe even with parts he has in his workshop.

I don't think I am allowed to share contact details on the forum, should be able to PM them if it will help you?

Cheers

Hi people. I can get n complete motor. But its a 1100. The mounting are the same as my bike. Engin number starts with kzt10b. Can someone tel me of witch bike this comes and if it is beter than the early j motors. The ouk wants 3000 sa rands or 300 odd dollars.

deanbyron wrote: Hi people. I can get n complete motor. But its a 1100. The mounting are the same as my bike. Engin number starts with kzt10b. Can someone tel me of witch bike this comes and if it is beter than the early j motors. The ouk wants 3000 sa rands or 300 odd dollars.

O the motor had fuel injection on but is not availible. The rest of bike was sold for scrap.

zedder.com/Info/83%20ZX1100-A1%20GPz.htm

perhaps.

leon