big bore

If I go 1395cc with a big block would I have problems?

Street motor 10.25:1, or drag 13.5:1 ?

Jay

1395 is a big motor. Cams, carbs, valves and port job development would have to match (Stage I, II, III). Not much sense in a 1395 block with stock cams, carbs or even valve sizes (early ZI/KZ). Chassis specifically rear wheel size better be able to match horsepower output. Machine work is likely needed on bottm end to get big block to fit. Wiseco is good for telling you what work needs to be done to fit parts. Keep engine development in step with itself. Don't go nuts on cc's and not be able to supply enough air/fuel to it.

Other than that the big issues would be a) Keeping underwear clean, b) Keeping license, c) Keeping wife/girlfriend/life partner.

what are you going to use it for?is your chassis ,brakes and tires up to the job?it doesnt take a whole lot of horsepower to bring out the weaknesses in the chassis/suspension in one of these bikes id recomend dealing with that before stuffing a mountain motor in there!

Post edited by: wireman, at: 2005/12/29 11:55

10:5:1 Street rodd!

You will not have a problem if everything is done correctly. You have to remember that the stock head is not even adaquate for a stock displacement motor. Therefore you will need to do a head with at least 37.5 / 31 valves and a real good port job, and run 435 cams and 36mm carbs.

Altho the head still won't be adaquate for high rpm, it will be a read tractor motor, gobs of low end and mid range, which can be real fun to ride on the street. Really surprise some guys on new sportbikes doing mid range roll ons.

I would suggest doing 1327cc because it is the same cylinder with thicker sleeves. You won't notice a performance difference because of the head, and if you ever damaged the pistons, 1395cc would be a simple rebore.

We do an awful lot of these big street packages for KZs, and can let you know things you will need to make it work.

One thing you might consider is locating a good J model cylinder head to use. It is a much better head and can use 38.6/33 valves without having to change the seats.

Check out our "Street racer" kits hers;
kzzone.com/kits.html

Jay

wireman the big bore will be used for street/strip and to shock a rocket:whistle:

kz-mtd wrote:

wireman the big bore will be used for street/strip and to shock a rocket:whistle:

just remember the slowly progressing rocket is also getting a 1385 but its gonna also have a turbo,injection and juice.and it will be a streetdriven rocket:evil:

Is overheating an issue here?

not so much with the turbo since when youre idling its basically an 8:1 motor,verses a 10.25:1 carbed motor which will have a constant compression whether its idling or wound up.