HP increase 24mm VS 29mm Smoothbores

On a good running stock Kz650 with pods and a 4 into 1 what do you think the power increase would be going from the stock 24s to the 29mm smoothbores?

how big are the ports on a 650 compared to 900-1000?

wireman wrote:

how big are the ports on a 650 compared to 900-1000?

Lot smaller.

I'd be willing to bet that ridability will suffer if you put 29's on the stock 650.

maybe try some 26s on there instead.

i thought about 29's for my 650 and was talked out of it. like wireman said in not so many words "can't go if it don't flow" i went with the 26's. noticed a little improvment.i also hade to custom the manifolds to fit the small bolt patern on the 650 head.let us know what you decide and how it turns out for you.

Wireman, Steell, and Kawsakiman Thanks much for the reply.

Bought the 29s new already way back in the early 80s (used 900 manifolds to mount) and have been running them until I sripped a drain plug in them 3 or 4 years ago. Put the stock carbs back on at that time and thought there really was'nt much of a change. Was happy with the low and mid range responce after a little jetting (on the 29s) but it just seemed like there was not much of a pick up on the top end.

After reading much on here I've come to realize I've run them both way to rich on the mains (120s) on both so I've got a set of 110s and 112.5s in the mail from Z1 along with new drain plugs so I will try them both with this set up.

I agree with you all that they probaly are to much for a stock set up and will probaly run the 24s but honestly I've always planned (dreamed?) of a 810 or 831cc kit so...

Sorry guys will take the 29s to my grave (so please don't ask) but you might be able to talk em out of my wife. Thanks again.

hell, i need 29's for my big bike. (i'm hoping your wife is sitting besides you reading this with you)

Post edited by: kawsakiman, at: 2006/09/25 18:52

"Hey KZB2 650, come down to my basement and check out all the NOS 650 parts I have. Sorry the light doesn't work so watch your step. I will follow you down. BOOM. hahahahaha". Dibs on the 29's guys.

Sorry kawtoy. I have just been appointed a homicide investigator. Here's a quarter, call your lawyer from the padded cell down at the station and of course...I'll have to seize those 29's for evidence:-)

Oh, by the way keep an eye out on ebay for a set of 29's with a low buy-it-now price!

Cheers-Colin Firth -Ontario Canada
1977Kz650 Custom with Wiseco 810 kit and lottsa go-faster goodies on board.

:laugh: You guys got me a thinkin about a safety deposit box or ay least a security guard.

Thanks for the replys and I'll try to improve on the double posts.