Super Jet Need help identifying sleeves!

CRJ

Hibernating
Location
Toronto
Hey,

Last season this top end blew due to my rookie mistake of not putting the C clip in correct (i believe). I am now trying to identify the sleeves to replace and rebuild it. The sleeves have a 90mm (+/- .05mm) outside diameter, and a 142.3mm (+/- .03mm) height. The were bored at 84.45mm. they are a 5 port plus exhaust sleeve. The bottom of the exhaust port to the bottom of the skirt is 68.3mm. my cylinder base to head surface height is 118.5mm. These are in 61x y-3 cylinders.

Can anyone give me an idea on what sleeve I have here and a suggestion on a replacement?

Thanks!
 

Th3g3rm4n4t0r

Brawlin' n Flippin'
84mm is stock bore on a 760, you have .5 over so that sleeve looks like its been reworked before. I also believe that my 760cc engine has a 64u bottom and a 61x - i think that all the cylinders are labelled 61x even IF they are 760.
 

yamanube

This Is The Way
Staff member
Location
Mandalor
If the bottom of the sleeve has a step in the OD or a groove around the bottom it is OEM, if it is one solid OD from top to bottom it is an aftermarket sleeve of some sort.
 

CRJ

Hibernating
Location
Toronto
Solid OD from top to bottom. i know they were bored to 84.5mm. i also know these cylinders were bored and resleeved and ported. are the ports from a 64x or other 760 cyl the same? Maybe its a 1200 sleeve from the yamaha triples?
 

yamanube

This Is The Way
Staff member
Location
Mandalor
The 1100/1200 monoblock NPV triples use the same 62t 701/760 sleeves and have a groove cut around them. As far as I know, no OEM sleeve has a constant OD, sounds like they are aftermarket sleeves of some sort and being a solid OD could likely be run out to 86mm (don't hold me to that). Why are you looking to replace them, are they cracked or damaged beyond an overbore?
 

CRJ

Hibernating
Location
Toronto
Yes the c-clip came out, taking out pieces of the sleeve and migrating to both cylinders through the exhaust cracking both.
 

yamanube

This Is The Way
Staff member
Location
Mandalor
Yikes, your best bet would be to put the cylinder in the oven and get the sleeves out and see if there is anything stamped/engraved in it to help identify. Otherwise, if we can get @#ZERO in here, he can likely tell you the manufacturer based on port height and OD alone. Some pictures might help as well.
 
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CRJ

Hibernating
Location
Toronto
ill get the sleeves out. whats the temp/time to bake them? press out or will they slide out? ive never pulled sleeves.

edit:

im reading 400 for an hr, ill try it maybe tonight. i guess ill clean them first too to avoid "smells" =D
 
Last edited:

yamanube

This Is The Way
Staff member
Location
Mandalor
ill get the sleeves out. whats the temp/time to bake them? press out or will they slide out? ive never pulled sleeves.
I'd go with around 400F, ideally if you have them right-side-up in the oven the casting will drop and you'll hear it. If after 30 minutes, they don't, grab them out of the oven and hit the casting with a rubber mallet. The fact that your sleeves are cracked might cause you a bit more work.
 

CRJ

Hibernating
Location
Toronto
does anyone know if the ports on a 701 61x and 1200 triple sleeve match each other? Its looking more and more like these are a 1200 sleeve, but i dont have any to check them against.
 

yamanube

This Is The Way
Staff member
Location
Mandalor
The 1200 sleeves are the same as 760 sleeves as far as I know.
Can you get a well lit photo of the bottom of the boost port?
 

CRJ

Hibernating
Location
Toronto
we pulled the sleeves and found they are close to a pair of 1200 sleeves. Top of the ports timing is the same, just opening up thin area on the 1200 cylinder. Now my next question is who makes a good quality sleeve that is smooth bore OD?

Thanks!
 

yamanube

This Is The Way
Staff member
Location
Mandalor
Those pictures really look like they are OEM sleeves and are not a constant OD all the way down. There are many companies that sell new sleeves but if you are replacing OEM sleeves with aftermarket sleeves, you will likely have to bore the cylinder casting to accept the new sleeves and likely the cases as well.
 
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