Very cold natured

Just purchased a 1980 Kz 1000. I have no complaints other than the fact that the bike takes nearly 10 miles or so to completely warm up. After this lengthly warm up period the bike idles great and runs flawlessly. I also seem to be getting much less than the 41mpg that the bike claims to achieve. Any insight on this matter would be greatly appreciated.

welcome to KZR
some of them are like that, the 650 will run on half choke for a bit until it warms up, I suppose some carb adj may help but I havent messed with it.

Post edited by: BSKZ650, at: 2007/10/17 07:36

Hi Volkton, welcome to KZr!

I know nothing about 1000's but I do know a little about poor gas mileage. Especially if you have a vacuum petcock . Adjusting the carbs will probably help and maybe a winter project, but if you have a vacuum carb, check this next time you go out. After running for a while and stop, pull your vacuum line off the carb and see if you have any gas leaking out of it. Last year I was only getting 23 mpg on a 400! It was driving me nuts until my mechanic discovered the gas leakage past the petcock diaphram. I then paid way too much for a new diaphram (not Rat the mechanics fault, I saw the invoice), but my mpg is now up 46 mpg which I can live with. I'm currently working on a KZ750 and will be curious what kind of mileage I'll get out of it.

There's probably quite a few more reasons for poor mileage....but that's the one that bit me.

Good luck! Oh yeah, pics please! :laugh:

There is a good chance that a 1980 model bike has sat for an extended period and the pilot and/or choke circuits are gummed up with gas deposits. The passageways associated with the flow of air and gas for these circuits are smaller in diameter than the the main circuits and consequently, any need for cleaning the carbs properly will more likely show up in hard starting and slow warm up and possibly, poor idle.

You may also need to adjust the carburetors idle mixture and last, the 41 mpg you say is "claimed"... who claims that again? That is on the high side for a 79/80 KZ1000 of most any type. Since your carburetors are pretty obviously in need of some cleaning and/or adjustment, it stands to reason that other tune up issues might help your gas mileage as well... I would say mid to high 30s would be more realistic (I have have several 79/80 KZ1000s myself). I suggest you have a look at the "Valve Clearances" and "Coil Repowering" articles on our website under "wg's Tech Stuff Index" as they might both help.

Since you gave no history for this bike, I suggest if you are not familiar with its history, to start by carefully checking the compression and then do a full tune up per the factory service manual and look at the tech articles I noted in the previous paragraph.

I'm getting 45 mpg on the highway with my 77 KZ1000. That's after I had a local guy sync my carbs. - Also that's 80mph for most of the trip, 100 miles - I'm pretty stoked with my milage.

The bike currently has 11k miles and the previous owner claimed to have had the valves adjusted and carbs cleaned recently. When starting the bike cold It has to be choked but fires up instantly. It seems that no matter how long I warm the bike up at a stand still it doesnt want to idle on it's own unless choked,or throttled. When the throttle is released the bike will sputter, pop occaisonally, and die. If I take off it will be sluggish and sputter for a several minutes but eventually run like a bat outa hell and idle great. Just an hour or two of sitting and I'm back to square one. Thanks alot for the advice I will be posting pics soon. Where should I post the pics on this site?

I think I'm getting around 30 mpg on the highway maybe a little less. Im a pretty big guy though at 250lbs. Is this about right?

Post edited by: Volktron58, at: 2007/10/18 00:52