Leak Down Test (Don't Laugh!!)

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I knew your weren't serious.
But some people don't realize this.

The noise is not nearly as loud as the camera makes it sound.

By the way, your parts did ship today.
 
Jim,
It’s pretty obvious that it took a lot of work to get click’s bike up to 880. I was courious to know if you start with a good engine at standard bore how much work would it take to get to 880 instead of going the 920 route using readily available parts (if these parts actually exist)

Pete
 
Deets55 said:
Jim,
It’s pretty obvious that it took a lot of work to get click’s bike up to 880. I was courious to know if you start with a good engine at standard bore how much work would it take to get to 880 instead of going the 920 route using readily available parts (if these parts actually exist)

Pete
Click to expand...

Click's project was more work because it was already a 920 with oversized wrist pins.
Fitting the big wrist pins into the readily available JE 880 pistons was not a job I will be doing again.

The 880 kit requires sleeves in the cylinders. The 880 sized bore is the largest I would use if you are looking for durability.

The JE pistons for 880 bore are readily available. They come with the problems created by a high expansion forged piston in an air cooled motor.

I can also get 4032 billet pistons on a special order basis. They are much more forgiving than the 2618 alloy pistons.

Before I would spend the money for a big bore kit I would do a cam and big valve conversion. You will get a lot more bang for the buck.

The power increase from a big bore kit without improving the breathing is very small.
 
comnoz said:
I knew your weren't serious.
But some people don't realize this.

The noise is not nearly as loud as the camera makes it sound.

By the way, your parts did ship today.
Click to expand...

Great, thanks for the update.
 
Another minor update:

Got the barrels and pistons/rings from Jim.

I've cleaned the barrels as per Jim's instructions. Clean with soapy water, let dry then wipe with kiitchen cloth & engine oil until no more black marks on kitchen cloth.

Fair amount of black 'stuff' on the cloth, took 3-4 rubdowns before the cloth was clean.

Next stage is to make a board for holding the barrels, fit the rings to the pistons, fit pistons into the barrels then fit the barrels/pistons to the conrods!!!

I know you guys like pictures so here's a very exciting picture of some buckets of hot soapy water & the barrels:)

Leak Down Test (Don't Laugh!!)
 
Need help already :rolleyes:

OK, I have the JE pistons & rings. I've gone to their site & looked at the install rings info. but it's not really helping!!

There's 3 rings, ones black, ones a copper colour & the 3rd is the 3 part oil ring (see pics below)

Does anybody have any better install instructions? For instance which one is the top ring, black or copper.

They both have N50 on them, see pics below, do these face up?

Also any help with the 3 part oil ring would be appreciated, especially any pics of a set installed.

What else would anybody be doing than helping me on Xmas eve!!!

By the way Happy Xmas to one & all on this forum and a very Happy New Year :D

Leak Down Test (Don't Laugh!!)
Leak Down Test (Don't Laugh!!)
Leak Down Test (Don't Laugh!!)
Leak Down Test (Don't Laugh!!)
Leak Down Test (Don't Laugh!!)
Leak Down Test (Don't Laugh!!)
 
Mmmmmm, Soapppy waaaaaatttter :oops:


Happy Christmas Click !!


Cheers,


cliffa.
 
I had these instructions with mine.
 

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Copper colored is the top
Black is the second
Numbers, letters or dots always face the top of the piston.
Install the oil ring with the side rails staggered one inch on either side of the expanders end.

Merry Christmas!!!
 
comnoz said:
Copper colored is the top
Black is the second
Numbers, letters or dots always face the top of the piston.
Install the oil ring with the side rails staggered one inch on either side of the expanders end.

Merry Christmas!!!
Click to expand...

Thanks Jim, have a good Christmas break.
 
Thought I had a few base gaskets in stock but I gave them to a mate over a year ago who was rebuilding his motor, he was suppose to replace them!!

By any chance if anybody from Ireland is reading this and has an 850 base gasket lying around drop me a PM.

I'm going to order some gaskets from the UK but I probably won't get them till 8/9th Jan!!

I know there's different opinions about using a base gasket or not but the motor had one fitted so I just want to replace like with like.
 
You don’t need it. Or more correctly, it should not be there on an 850.

Putting it in just because it was there before is a strange logic matey... you’re not putting the other ‘errors’ back in are you!?

Putting one in will only lose you a little bit of CR, that’s all.

I’d press on without it.
 
Fast Eddie said:
You don’t need it. Or more correctly, it should not be there on an 850.

Putting it in just because it was there before is a strange logic matey... you’re not putting the other ‘errors’ back in are you!?

Putting one in will only lose you a little bit of CR, that’s all.

I’d press on without it.
Click to expand...

I know we are talking about a very minor clearance difference between using & not using a gasket but could I have any issues with pushrods/tappet clearance etc? Sort of know the answer, just want to be sure!!
 
click said:
I know we are talking about a very minor clearance difference between using & not using a gasket but could I have any issues with pushrods/tappet clearance etc? Sort of know the answer, just want to be sure!!
Click to expand...

Be sure about what Click...? The 850 DID NOT HAVE a gasket from the factory. So, unless your pushrods have been shortened to accommodate the thickness of a gasket by the previous builder (rather unlikely I’d suggest) then by your own argument, you’re better off without one...!

Jus’ sayin’...
 
Fast Eddie said:
Be sure about what Click...? The 850 DID NOT HAVE a gasket from the factory. So, unless your pushrods have been shortened to accommodate the thickness of a gasket by the previous builder (rather unlikely I’d suggest) then by your own argument, you’re better off without one...!

Jus’ sayin’...
Click to expand...

Thanks for the reply, what I've found is that the 850's up to the MK3 did not use a base gasket, but they reinstated the use of a base gasket on the 850 MK3 (which is what I have)
The main reason they reinstated the use of the base gasket, owners were using too much 'gunk' & plugging up the oil return hole!

I get your point so no need to shout :rolleyes:;)

Some guys have rebuilt without a gasket & have had no issues but some have had niggling leaks, which when rebuilt with a gasket have gone away.
 
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