Hi and welcome to the forum. I looked at the JE piston box that came with the BB331 kit and it says BORE 3.2677, this converts to 82.9995 mm. Damn near 83mm if you round up...haha

 

Thanks so much!

But you know from each bike is it designed? because I took a look at je catalog an can't Find any Klx big bore piston

 

Wow, old thread. Almost 6 years now? I feel old.

 

A little bit old, haha buthere in Brazil , klx 250 sf is a 2010 bike. I'm trying to get more power on my bike. I tried to get some ansower from kustom kraft by sending emails, but i got no ansower. Does kustom kraft still exist? No brakes, do you own this klx yet? It still works fine with this 331cc engine? Do you recommend use it? My bike is an efi version, like the European one. Do youknow something else i will need to do? Thanks so much

 

I wonder if they do international sales to your area or maybe they don't do any international sales. I don't know, but it might have something to do with the lack of response. I think one of the other members on here is doing a 331 KK kit right now, so I expect they're still in business.

 

I sell the 331 kit for $499.95 MUCH less than the same kit from KK.

 

I no longer own that bike, it was purchased by another forum member here in '07, and I believe he sold it to yet another forum member a few years later. To the best of my knowledge, it is still running fine, but I haven't kept up with it, maybe the current owner can chime in if he sees this.

On the EFI, I'm guessing that might complicate things, since you would need an external tuner something like a power commander to richen up the mixture to account for the larger displacement. With a carb'd bike you can just swap jets and needles.

Also, I believe Kustom Kraft is still in business, but don't quote me on that.

Good luck!

 

I can confirm Kustom Kraft are still in the big bore game. I acquired a 331 kit about 5 months ago! The only change from the website advertised BB kit content is the JE piston has been replaced with a German Wossner piston.

KK use a brand new klx300 cylinder which is bored out & nikasil plated.

 

It's not really the same thing. KK come's with a brand new cylinder. Your kit does not based on prior posts.

A Bill Blue 331 kit is only $486.95 which is cheaper than yours!


Posted by cpr1 on 2-26-2012

My 331 kit is identical to the KK kit, and it only costs $499.95 with cylinder exhange. Yes it's Nikasil and not a wet liner. I have one in stock at the moment.

 

Someone know about this wossner piston? That's a good deal? I need one new cylinder, cause i want to keep my 250 cylinder. Does someone of this big bore kit don't need exchange the cylinder?

Thanks