Been off the forum for a while due to being busy goint on working/fun trips and trying to scrape together some $ to buy land.
A month or so ago I had red temp light and boilover out of puke tank. Filled the bike up after it cooled off and started it again. Exh bubbling up in the puke tank and a bit of oil. Also had water in the oil.
I assumed it was blown head gasket. Since I am so isolated out here I decieded to upgrade from the KK330 to BB351 with smog blockoff while I was at it. I was not sure if the cyl and piston would be scored up but did not want to order only gaskets and then have to wait for more parts to come in. Turns out when I took of the head and cyl this sunday I found a crack in the cyl. Comeing down from the top about 2/3 the way down. I think this crack had developed before becuase I had felt a small loss of power, adjusted the valves and still no difference.

So if anyone wants my take on a bill blue kit with sleave or Kustom Kraft bore job with nikasil plateing I would recomend the BB. Have not heard of a failure yet.

On the KK I bought the bike used with it installed and a FCR35 also. I put about 10,000 hard earned miles on the bike. I dog it hard. Mostly streat with a few days of dirt. All in tropical heat. Never noticed any drop in the coolant level until the fateful day(spent about half hour in stop and go trafic on a very hot day) There is NO scoring at all on the cyl walls and piston looks perfect. In fact I thought the crack was a scratch was going to decide if I should ignore it and install on the GF's bike or not.

I Will try and take some photos and post later on in the week.

Cheers Jim

 

Sorry for you.
Thanks for the info.

 

wow thats some news. sorry to hear.

 

That's a bummer. That nikasil is supposed to last 3 times longer than the steel sleeve. Is there not a lot of meat between the sidewall of the cylinder and the water jacket? There was a guy on here the other day that had a crack in his new 351 sleeve. Shyt happens, especially after eating at Taco Bell.

 

The Nikasil SURFACE is supposed to last many times longer. But, reading the KK site, it costs more than a sleeve. And, it's only warranted 1 year, where the sleeve is warranted 5 years...and, again, the sleeve is cheaper.

That info led me to get the BB sleeve.

Sorry for your trouble....

 

It does make you wonder about the bored and plated version's structural integrity. You're running in nothing but thinly plated aluminum. I don't think that's any issue with a cylinder thickness designed to do so, but it makes you think about how thick and tough a bored and plated cylinder might be.

 

Sorry for your blowup, but if you got 10,000 miles out of a secondhand bored & plated cylinder with hard use in tropical heat, I'd say you got your money's worth. For a serious weight weenie that would be well worth the chance of a potential meltdown. I'm with the other guys, though. I'd rather have the reliability at the cost of a pound or two. When my stock setup wears, I'll go with the Bill Blue sleeve.

 

I did not see the post from the guy with the cracked 351 Thats too bad as I was hopeing to not have the problem with 351. I figure I am fairly hard on the bike but I expected more than 10K on the second hand 331 after it made it thru the first 3K and doubled the milage to 6K. When I looked at the KK it looked pretty thin walled. But I will say the cyl walls were very smothe so I am sure the nikasil plateing was working fine. I think it was just heat cycles/fatigue.

I am not sweating the cost as I have saved so much more in fuel costs that any money I put in the bike is still a saveings and I enjoy driveing the bike more than the truck in trafic & anything other than rain.

I was jut putting the crack out there as a FYI for anyone on the fence.

Cheers Jim

 

honestly, Jimbo... I would just say you've worn it out. Technically this is a dirtbike and a small bore one at that, so 10K miles is a lot!

 

Thanks for the info maninthesea, I think everyone should should post info like this. I'd say 10,000+ hard miles in tropical heat is a pretty good showing for the 330 cylinder. Since the BB kit is cheaper, I don't blame you for going in that direction. If I ever decide to do the barrel upgrade, I'd probably go for the sleeve too (less $$, more cc's).