350X with 460cc???

[Extremesounds13]

Got a 350X question for everyone: I went and looked at a 350X that is for sale south of here the guy says it has a Thumper big bore kit in it that punched it out to around 460cc, he said he had the kit done about 5 years ago and said it cost him around a grand to do it. I rode the trike around and it has mad power:w00t: way more than my 350X that I just did a new top end in. So my question to everyone is: is the 460cc thing true, is that possible. I just want to know before I make him any sort of offers on the trike. Thanks

[The Goat]

multiple people make big bore kits for the 350x. I'd ask him who did it...is it all in just a larger cylinder...or is it stroked. What was done to increase flow in the top, a bit of polishing, a new head, a highlift cam...what?

a 452 kit, a hi performance cam, port, polish, hard faced rockers, and stronger valve springs will run you around 900...if you do the work yourself.

[Extremesounds13]

the guy said it was not stroked, he said there was a cam, and it has (from what I can tell) quite a bit bigger carb on it. He said the brand was thumper, or something like that. It didn't ring a bell to me but I thought someone on here might recognize it or something similar.

[Rustytinhorn]

Hey, Dont you steal my 350x....lol
I saw it for sale too, wish I had $$ to buy it.

I didn't realize you were soo close. Do you ride St. Anthonys?? If so. next time I go I will have to look you up.
You didn't sell off a 250r a year ago or so by chance did you??

[Extremesounds13]

What part of utah are you in? what year 250R was it, I sold an 83 about a year ago.

[Rustytinhorn]

It would have been an '85. Just wonderin cuz my bike was from Idaho.
I'm in Northern Utah, up by Brigham City/Logan area. Thinkin of coming up to St. Anthonys in June if I can manage it. Also want to drag another buddy along too if it all works out.

[SWIGIN]

my buddy just got his 460cc 350x motor done and im building one too.....they do run real strong but we did it with a 89mm piston and a stroker crank (89mm bore 6mm stroker)

so yes there is such a thing

[lndy650]

the 350x has a really long stroke already so i just bored mine no stroker its a 452cc to get more high rpm power rather than the long stroke torque (it still has crazy torque) it cost me about $400 then i welded up my own cam and ported my head. i should get the hard face rockers and heavy duty valve springs though.
i have a head and cam done by Tom Carlson to go by...
i have heard from people in the know that these 352 kits with porting and a cam make 40hp!