Super Jet big bore sleeve options

[trojoro]

i have been looking into installing a big bore top end onto my 701,i was looking around and have found that many people offer reasonably priced big bore sleeves. What do you guys think of the blowsion sleeves, they seem like a pretty good deal.

 

[Dmac80sc]

Have you looked into what it takes to make your motor into a big bore? I was thinking of trying to do it too at one point. But the cases have to be fly cut to take the big bore sleeves. Pretty sure the cylinder needs to be opened up to take the big bored sleeves and then some porting will need to be done. It is a good bit of work to be done.

 

[trojoro]

yeah am pretty aware of what it takes from looking into other peoples builds. And I'm just looking into all options right now. I would love to be able to afford a professionally built motor but thats just not an option for me. I was looking into the blows ion pre ported 785 sleeves. at 280 for a set they seem pretty reasonable and the oem 753 yamaha pistons can be used. From what i understand i will have to fly cut the cases, press in the sleeve, match the ports, and run a 760 head. I'm sure there a whole lot more work than i just listed but it seems like for around 700 dollars i could have a pretty powerful engine.

 

[zzylstra]

Subscribed, also looking into doing this

 

[d_moss]

LA sleeve makes them or I think its North west sleeve makes some also. If you want to buy direct. Doing the 850 BB 62t cylinder it was not cheap. I have a build thread that shows all the deatails and problems I ran into.

The 780 61x would be way cheaper unless your square has the stock 62t in it. then you dont have to buy a new cylinder to bore up to 850 like the 61x (not enough casting material).

850 pistons cr500 pistons work with a lot of work. or custom ones and group k might still have some in stock $180 a piston I think.

I have left over 760 sleeves that I think slide into a 62t cylinder with no machining. Just port it and ride it. Pm me if you are interested.

But check out my build thread I think its in ski build ups under 850 big bore and color change some thing to that effect.

 

[chriselmore_1]

Don't use la sleeves. Northwest. Or watcon. Watcons sleeves ate actually northwest sleeves but pre ported to randys specs. Not really sure about the porting specs of blowsions sleeves. It would be a good idea to open up the intake Ports and Poiret the cases too. In. pretty sure northwest will install a pair of sleeves and portmatch for about 500

 

[trojoro]

i do have an extra cal thats a 62t, but i am leaning towards the 780 due to it being so much cheaper. As of now i have 61x cases, should i switch over to 62t cases or keep my 61x and run dual 44s.

 

[trojoro]

with the pre ported sleeves from watcon or blowsion just need to be installed and the ports of the cyl need to be matched with the sleeve by grinding the aluminum cyl smooth with the sleeve

 

[d_moss]

yes and blowsions at least the 850 are north west sleeves. They might "port" them though. But all it really is, is make the intakes bigger and the exhaust port was lower than the 760 cylinder casting but a lot wider. Before and after pics in my thread.

I have blowsion/north west and they seem to work fine... Blowsions are a fair price i though but the machine shop said I paid a lot for a sleeve. So idk.

 

[egbrig]

Get the WATCON sleeves. They are made by Northwest to WATCON specs. NW uses a much better iron for their sleeves. You can see the difference when boring a NW vs. LA. What I like about the WATCON sleeve is the flange at the top. Its width lets the head dome O-ring (most heads are O-ringed today) sit on an all steel base and it gives a better sealing surfice.

 

[trojoro]

Get the WATCON sleeves. They are made by Northwest to WATCON specs. NW uses a much better iron for their sleeves. You can see the difference when boring a NW vs. LA. What I like about the WATCON sleeve is the flange at the top. Its width lets the head dome O-ring (most heads are O-ringed today) sit on an all steel base and it gives a better sealing surfice.

After looking on the watcon site i would rather go with randys sleeve.

 

[#ZERO]

If you have a 61X cylinder using the stock stroke crank with the oem type pistons there's only two options for the best performance and the would be my custom made NW 61X big bore sleeves or the Jet-Blue NW sleeves in my opinion.