Crank seals

becky · Post by **becky** » Wed Nov 28, 2012 8:37 pm

Hi, I'm just about to strip a KR1 engine down for a mate, because I suspect the crankshaft oil seal has failed. The exhaust on the rhs is smoking bad even after a good run and it has oil leaks from most oil seals on the engine
( kick start, gear shaft, drive shaft and others ) so looks like crank case compression.
Now my question is this, can I just fit the two outer oil seals without having to have the crank re built. And if yes do you think the inner seals will be shot anyway. so would need changing with a crank rebuild..
Thanks Phil.

martin · Post by **martin** » Wed Nov 28, 2012 9:14 pm

am afraid the answer to your question is, you will have to have it rebuilt
by bdk or similer

fred · Post by **fred** » Wed Nov 28, 2012 9:32 pm

you`le soon find out when youve got the crank out ,it`s not hard ,if the inner seals spin without any friction there gone ,and you may find the bearings float ,dont fool yerself like i tried ,just bite the bullet n go for it

becky · Post by **becky** » Fri Nov 30, 2012 8:35 pm

Thanks Lads,
Now can you just tell me one more thing. What is the difference between the KR1 and KR1S engines, are gasket sets the same for both bikes? What will not inter change between engines ?
Cheers

Binetta Steve · Post by **Binetta Steve** » Fri Nov 30, 2012 9:38 pm

Hi Becky , im new to KR1S bikes but there are some definite differences you need to be aware of, i believe big K released about 5 bhp, through kips setting , exhaust, carbs. Have a look back through the section on 'engine' its gold plated advice.

Steve

ScottaKR · Post by **ScottaKR** » Fri Nov 30, 2012 10:39 pm

Engine differences are.....
-The engine cases themselves. This includes the balance shaft cover. There is one extra bolt on the underside somewhere, but can't quite remember where atm. Can be interchanged but should always be done as a matched set, or you can have trouble with gaps btween the faces.
-Barrels. Have different port timings and sizes. Can be interchanged, but should be done as a set for it to run at it's best, ie. either 2 KR1 barrels, or 2 KR1S barrels, not a mix of both (although it's quite common to see a mix of both on an engine that's been previously repaired by somone who dosn't care, or didn't know any better).
-KIPS valves. The KR1S has larger KIPS ports, and as such has larger (taller) openings in the KIPS valves. For best results you should run the correct valves for the barrels your running (although it's very common to find a mismatched set when you tear down an engine)
-Gearbox. Slight differences between the 2. The most obvious difference here (and one that can help you identify which engine you have) is the oil fill plug. On the KR1 it's an alloy item (which can seize) with a slot in it requiring a large screwdriver or coin to open, whereas on the KR1S it was a plastic item that you can easily grip and open by hand.
I believe that the boxes can be changed as a whole unit (I stand to be corrected of course), but internal parts should not be swapped between diferent model boxes as many differ very slightly.

Pretty much everything else in the engine is the same.
The gasket sets are the same. Generally, the pattern gaskets are fine except for the head gasket which has a tendancy to leak for some reason. Most people use the genuine Kawasaki head gasket, although some have managed to run the pattern one without issue before. For best results here most people use a sealant like H0nda-bond on the gasket surfaces just to be sure.

becky · Post by **becky** » Sat Dec 01, 2012 10:34 am

Thanks again. That is just what I needed.
Looks like I'm getting started this weekend with it.
Cheers.