Carbs for 1015cc or 1075cc Upgrade

Ooooo pretty! Now I have to port my head. Thanx. Oh well it will give me something to do until it warms up. :laugh:

Now I have to port my head

... Yup!!!

As explained to me by the man himself Larry C.... You can put the biggest, most expensive carbs on the planet on a motor and will it work, well ya but will it work to the true/full potetential of the carb/head design.... Hell no it won't...

Henceforth, even with 29-34's, to obatin optimum performance from your carbs/head, you need to open up the ports to match the itake openings for ideal air flow input and polish them to keep the turbalance at a minimum...

Welcome to the world of Port & Polish in the easiest form of explanation...

OMR

does anyone know if you can take a set of 1980 z1r 28mm accelerator pump carbs and bore them as otto suggested?if so do you know if you have to offset bore them or just bore them straight with the existing bore?just curious as i have the equipment to bore them,but no carb boring experience.
tia,

leon holmes

Or you could just...
cgi.ebay.com/ebaymotors/dragbike-kawasak...fPartsQ5fAccessories

AH JEAH!!!! Try to run that on the sreeet.:ohmy: I can pay for that out of my pocket change. :laugh: I wonder how many years of tax refunds it would take for me to pay for that. I think I will just take the 8-10 hours and port my own. (HUM is that like "roll my own"? )

531blackbanshee wrote:

does anyone know if you can take a set of 1980 z1r 28mm accelerator pump carbs and bore them as otto suggested?if so do you know if you have to offset bore them or just bore them straight with the existing bore?just curious as i have the equipment to bore them,but no carb boring experience.
tia,

leon holmes

Back in the day, when some of us could not afford to buy 29SBs, that is what was done. They could punch them to 28.6MM and they would be SBs. It used to cost about $50 back in the late 70s erly 80s today i imagine about $100+. They used to work very well, much better than the stock 28s.

otakar wrote:

531blackbanshee wrote:

does anyone know if you can take a set of 1980 z1r 28mm accelerator pump carbs and bore them as otto suggested?if so do you know if you have to offset bore them or just bore them straight with the existing bore?just curious as i have the equipment to bore them,but no carb boring experience.
tia,

leon holmes

Back in the day, when some of us could not afford to buy 29SBs, that is what was done. They could punch them to 28.6MM and they would be SBs. It used to cost about $50 back in the late 70s erly 80s today i imagine about $100+. They used to work very well, much better than the stock 28s.

ditto

So how exactly is boring 28mm carbs accomplished? Just disassemble them and run a big reamer through the bodies?
Is that it, or are there some other double top secret voodoo tweaks to be done too? Anything done to the primary and main circuits? Bigger jets?

I've also heard that these pumper carbs aren't very popular with the racers. True? Why?

i used to see it done to lots of early z1 28s, pumper carbs were more of a way to make up for epa rules

riverroad wrote:

Or you could just...
cgi.ebay.com/ebaymotors/dragbike-kawasak...fPartsQ5fAccessories

lol I bet those will go well with those Venom tires and the fluffy velvet seat from the bike that was posted in value of a performance build link.
I bet it would put a smile on your face.

Old Man Rock wrote:

Smooth-bore 28mm's, sure would love to have a set but have you seen what these have been going for on e-bay! That one set sold for $1000.... :blink: Not even re-built at that, nasty old set with stripped screws, missing pieces and such.... Totally bonkers... :blink:

One of the reasons I went with new vs 30 year old set.... The pricing was phenomenally insane not to mention for the majority of these old sets, parts are becoming hard to find... Actually obsolete in some cases....

Unless your sticking with 100% stock restoration for which I could understand the need for 28/29 smoothies, new carbs are the only way to go where by the time you find a set, re-build them and if your lucky you don't come across the WTF factoring or need obsolete parts, it breaks out about the same in costs...

Cro Dog bought those 29s and put them on his bike and they look really nice being that the old ones were harder to mess with. He has a set of original 28s if any of you guys are in to the originals drop him a pm I am sure he would be happy to help defray the cost of his new carbs. They weren't cheap but piece of mind is worth a small fortune.

The carbs that are on my bike measured 28.5 mm according to a micrometer, but they look like VM28's and not like any 29's I've seen pictures of.

They also don't look they have ever been machined.

I will have to double check when I have them off next.

I know they run great.:side: