Fixing Junk, Aftermarket cylinders

[Red97]

So.... we all know by now porting 98% of aftmarket cylinders is a waste of time.

(Cheap chrome white box cylinders port the best, but still have issue)

Little back story. Have an event coming up that is racing clone saws 660/372.... Cool, they also have firewood classes 55,65,85cc

So I got the ok to go down a bore size to 52mm and dual enter my 660 clone in the 85cc class and the clone 660 class.

I have had one of those fancy pistons with a chrome ring , I have been wanting to use it for a while now. To run a chrome ring you need a nikasil bore....

So I picked up a meteor, and hyway 650/52mm cylinders.



Both are identical castings. Meteor had harder /shinier plating. But both were nikasil.



Meteor had issues right at the base cut...


Hyway managed to port up ok, using a stone to open the ports.


Even made pretty solid power for 85cc aftermarket with no chamber work.

Then I decided to eliminate any questions, and just build a 54mm for the clone 660 and swap this 52mm on my oem 660 for the firewood 85cc class.

That is when I find...

Plating above the exhaust decided to leave the chat in less than 1 tank....

 

[Loony661]

So.... we all know by now porting 98% of aftmarket cylinders is a waste of time.

(Cheap chrome white box cylinders port the best, but still have issue)

Little back story. Have an event coming up that is racing clone saws 660/372.... Cool, they also have firewood classes 55,65,85cc

So I got the ok to go down a bore size to 52mm and dual enter my 660 clone in the 85cc class and the clone 660 class.

I have had one of those fancy pistons with a chrome ring , I have been wanting to use it for a while now. To run a chrome ring you need a nikasil bore....

So I picked up a meteor, and hyway 650/52mm cylinders.

View attachment 392336

Both are identical castings. Meteor had harder /shinier plating. But both were nikasil.

View attachment 392337

Meteor had issues right at the base cut...

View attachment 392339
Hyway managed to port up ok, using a stone to open the ports.

View attachment 392340
Even made pretty solid power for 85cc aftermarket with no chamber work.

Then I decided to eliminate any questions, and just build a 54mm for the clone 660 and swap this 52mm on my oem 660 for the firewood 85cc class.

That is when I find...
View attachment 392341
Plating above the exhaust decided to leave the chat in less than 1 tank....

No bueno. After all that work too..

 

[Red97]

Me being the stubborn fool I can be decided I am going to fix this problem....



Plating can't chip if it doesn't have any..


So I bore it 56mm and spin up an iron sleeve approx 2mm wall thickness.


Sleeve installed, bored and honed. Port heights installed


And all finished. Chamber work and all. If this plating chips we have big problems.....

Silly chainsaws who's idea was this fad anyway.

 

[Red97]

No bueno. After all that work too..

Yeh, was pretty disappointed. Good thing I decided to build a 2nd saw vs running that one. Never would have known.

 

[Ketchup]

Me being the stubborn fool I can be decided I am going to fix this problem....

View attachment 392342

Plating can't chip if it doesn't have any..

View attachment 392343
So I bore it 56mm and spin up an iron sleeve approx 2mm wall thickness.

View attachment 392344
Sleeve installed, bored and honed. Port heights installed

View attachment 392345View attachment 392346
And all finished. Chamber work and all. If this plating chips we have big problems.....

Silly chainsaws who's idea was this fad anyway?

That’s a slick job there Joe! Do you like the homemade sleeve better than a purchased iron one? Can you grind it with an Alumihog or does it need different burrs?

 

[farminkarman]

So.... we all know by now porting 98% of aftmarket cylinders is a waste of time.

(Cheap chrome white box cylinders port the best, but still have issue)

Little back story. Have an event coming up that is racing clone saws 660/372.... Cool, they also have firewood classes 55,65,85cc

So I got the ok to go down a bore size to 52mm and dual enter my 660 clone in the 85cc class and the clone 660 class.

I have had one of those fancy pistons with a chrome ring , I have been wanting to use it for a while now. To run a chrome ring you need a nikasil bore....

So I picked up a meteor, and hyway 650/52mm cylinders.

View attachment 392336

Both are identical castings. Meteor had harder /shinier plating. But both were nikasil.

View attachment 392337

Meteor had issues right at the base cut...

View attachment 392339
Hyway managed to port up ok, using a stone to open the ports.

View attachment 392340
Even made pretty solid power for 85cc aftermarket with no chamber work.

Then I decided to eliminate any questions, and just build a 54mm for the clone 660 and swap this 52mm on my oem 660 for the firewood 85cc class.

That is when I find...
View attachment 392341
Plating above the exhaust decided to leave the chat in less than 1 tank....

Classic Hyway & or Meteor failure.

 

[farminkarman]

Me being the stubborn fool I can be decided I am going to fix this problem....

View attachment 392342

Plating can't chip if it doesn't have any..

View attachment 392343
So I bore it 56mm and spin up an iron sleeve approx 2mm wall thickness.

View attachment 392344
Sleeve installed, bored and honed. Port heights installed

View attachment 392345View attachment 392346
And all finished. Chamber work and all. If this plating chips we have big problems.....

Silly chainsaws who's idea was this fad anyway.

Very nice work Joe! Thanks for sharing.

 

[Red97]

That’s a slick job there Joe! Do you like the homemade sleeve better than a purchased iron one? Can you grind it with an Alumihog or does it need different burrs?

Thank you

It is a purchased sleeve blank. They have them in various sizes.

They grind fairly well. A double cut burr really does well. Easier and smoother than aluminum really. Very smooth just a bit slower.

 

[Red97]

Few chips along the way.

 

[mrxlh]

Joe, I’m fairly certain this is the only economical way to repair unobtanium cylinders. The cost of blind bore plating has made it just about impossible to save cylinders no longer available. I hope you make a side business out of this.

 

[Red97]

Joe, I’m fairly certain this is the only economical way to repair unobtanium cylinders. The cost of blind bore plating has made it just about impossible to save cylinders no longer available. I hope you make a side business out of this.

Cost is about rhe same either way I would imagine. A ton of time into these. And some cylinders/blocks won't take a sleeve without cracking. Macs are bad about that from what I have heard.

 

[Red97]

All installed and ready to make some pulls. Did notice my oiler worm was broken.

 

[Darryll]

Hi Joe. I'm interested observations regarding finger porting. How they effect the power on the dyno etc.

 

[Red97]

If anyone wants to watch this cylinder build. Engine noise/ Dyno pulls at the end.

 

[Red97]

Red line is clone g660 ported hyway full timing advance/most powerful pull.

Blue line is iron sleeve, first pulls, stock timing on my late ms660. I'm thinking some advance may wake it up.

 

[legdelimber]

Wow. The Meteor cylinder looks like it was sleeved with a drink can.
You have to wonder what sort of heat transfer and piston issues that cylinder would have.

 

[Red97]

Working on finding some more power from this little critter.

 

[farminkarman]

View attachment 392626

Working on finding some more power from this little critter.

Very nice Joe!

 

[Al Smith]

I just mentioned Joe on another thread and danged if he doesn't show up .About sleeves .IMO cast iron is the way to go ,it's worked for years and you can use tool steel piston rings .As far as heat transfer I don't think it's a problem .With a heat/shrink press it won't come out unless you bore it out--been there and done that having made the liner a tad off of OD and cracked the stinking sleeve installing it . Once again proving even if you know just about everything everybody screws up now and again --guilty as charged----

 

[mrxlh]

Using cast sleeves you can use chrome piston rings, which last a long, long time…