Hi everyone, this is my first post! I’m needing some help deciding what to do I recently resurrected one of our old blasters that we blew up 5-6 years ago from the back pasture graveyard lol I wanted to get it going again for something to just be able to cruise around on so I did everything as cheap as I could. It has a Vito’s big bore kit on it and when it blew up last time it just seized the piston and melted the rings. So wanting to do it cheap I just ordered rings for the piston, put them lightly honed the cylinder and got it going. Well after dialing in the jets I didn’t even run a full tank of gas through it before blew the piston into 5 pieces and locked up solid lol so now here is my problem I still am wanting to stay cheap. But I’m absolutely torn on keeping the big bore kit having it bored and going up to the next size piston, which is the last size it can be bored before it needs a sleeve (73mm). Or Buying a stock oem cylinder, wiseco piston and going back to everything stock. My blaster currently is running a 35mm Keihin pwk. Has +4 degree advanced timing key, full fmf power core exhaust, Vito’s performance reed cage and carbon fiber reeds. I want something that is gonna be reliable Enough to go on longer trail rides but at the same time I like to rip lol my gut tells me to go back to stock and be safe rather than sorry but my head says “let’s go fast” lol the thing with the Vito’s kit that I’m more nervous on is I don’t know the exact tolerance that it needs to be bored out to neither does my local machine shop. Therefore any input will be appreciated on what to do. Thanks guys!
Vito’s big bore kit or go back to stock
- Thread starter Benjimen3
- Start date
The Vito's kit can be just as reliable as a bone stock cylinder/piston ...... with proper jetting and basic maintenance.
your failure began with a ring replacement on a worn bore/piston, and will most likely cost you more now
as not only will you need to rebore that cylinder and new piston, but you now probably have piston shrapnel in the bottom end and bearings, which will require splitting the cases and at the very minimum, with fingers crossed, flush every speck of it out, including in the bearings, and hope you don't miss any. any leftover shrapnel or a future bottom end failure will take out the new top end also.
if I were splitting the cases, I'd at least put new main bearings and seals in it at minumum, and have the crank rebuilt too.
but roll the dice if you choose ?
I'd stick with that 240 cylinder as you already have the carb/intake to run it
what pipe and was the carb jetted for it ?
I also suggest a leakdown test when you get it back together, an airleak will quickly fry a new top end and snatch more $ out of your pocket
as for the piston, it will have the clearance listed on a sheet inside the box. cast vs. forged require different clearances.
If your local shop still questions anything, send it here like alot of us do, worth every penny of shipping to know it's done 110% correctly ...
http://www.kenoconnorracing.com/
your failure began with a ring replacement on a worn bore/piston, and will most likely cost you more now
as not only will you need to rebore that cylinder and new piston, but you now probably have piston shrapnel in the bottom end and bearings, which will require splitting the cases and at the very minimum, with fingers crossed, flush every speck of it out, including in the bearings, and hope you don't miss any. any leftover shrapnel or a future bottom end failure will take out the new top end also.
if I were splitting the cases, I'd at least put new main bearings and seals in it at minumum, and have the crank rebuilt too.
but roll the dice if you choose ?
I'd stick with that 240 cylinder as you already have the carb/intake to run it
what pipe and was the carb jetted for it ?
I also suggest a leakdown test when you get it back together, an airleak will quickly fry a new top end and snatch more $ out of your pocket
as for the piston, it will have the clearance listed on a sheet inside the box. cast vs. forged require different clearances.
If your local shop still questions anything, send it here like alot of us do, worth every penny of shipping to know it's done 110% correctly ...
http://www.kenoconnorracing.com/
The Vito's kit can be just as reliable as a bone stock cylinder/piston ...... with proper jetting and basic maintenance.
your failure began with a ring replacement on a worn bore/piston, and will most likely cost you more now
as not only will you need to rebore that cylinder and new piston, but you now probably have piston shrapnel in the bottom end and bearings, which will require splitting the cases and at the very minimum, with fingers crossed, flush every speck of it out, including in the bearings, and hope you don't miss any. any leftover shrapnel or a future bottom end failure will take out the new top end also.
if I were splitting the cases, I'd at least put new main bearings and seals in it at minumum, and have the crank rebuilt too.
but roll the dice if you choose ?
I'd stick with that 240 cylinder as you already have the carb/intake to run it
what pipe and was the carb jetted for it ?
I also suggest a leakdown test when you get it back together, an airleak will quickly fry a new top end and snatch more $ out of your pocket
as for the piston, it will have the clearance listed on a sheet inside the box. cast vs. forged require different clearances.
If your local shop still questions anything, send it here like alot of us do, worth every penny of shipping to know it's done 110% correctly ...
http://www.kenoconnorracing.com/
Thanks for the reply awk! Are you asking what jets I had in it? If so I had a 158 main that’s where it seemed to be running it’s best and after 2 plug chops it’s was a milky tanish brown color. I’m glad to hear you say stick with the Vito’s. I will probably get a new piston ordered and start the process of Sending it to ken. Would you recommend having him port it as well while he has it? Thanks!
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