Love this site!

Being a 300zx and Maxima owner, I was so thrilled to see that there is an enthusiasts' site for my newly aquired 1980 KZ750 H1, just like there was for my beloved autos.

Being a very new but eager "club member" I am hoping to pick up as much as I can from this site.

This is my first street bike (motocross while growing up). It was traded to me as a debt payoff from someone who knew a shop guy who got it from... you get the idea. As you can imagine, the condition is anything but fair as it's been sitting for quite a while. I have no history to report other than I'm pretty sure nothing serious ever happened to it.

I've spent many hours combing this site looking at some how-tos and guides but it's tough to know where to start.

Here's where I'm at:
She cranks just fine, but will only turn over while choking it and giving her a little gas. She will only remain running with a little throttle. Letting go of the throttle and she stumbles out.

I live in the Northeast USA and although the season is almost over anyway, I have ZERO time during the week for troubleshooting, so I want to make the best of every weekend.
Is a carb removal/cleaning the best first step here?

Here's another newbie question. Like cars, can you troubleshoot dead/problematic cylinders by just pulling a sparkplug wire off and listening for a change in rhythm?

Thanks in advance!

Yep, this is the place to be. I'm not ready to give much advice, but there are a lot of members here that will guide you in the right direction. Welcome and good luck with the bike!

Yea, after sitting for awhile the first step would be to remove the carbs. A complete cleaning is in order, all passages, jets, pilots, etc. 2-3 year old gas does wonderful stuff inside the carbs. Then check or replace points. Check valve adjustment. (Lots of fun) This should put you in the "ball park" as far as running. Change oil and filter and if running OK, do a complete safety check before hitting the road!! Redo your compression check after it is warmed up, if the same put about a teaspoon of engine oil in the low cyl and if compression rises it's rings if not it's valves. Any questions, we're here for ya! By the way, as a member of KZR, you ARE required to provide pictures! :whistle:

With a bike that's been sitting for a while, a good carb cleaning is a good place to start. Also, check your valve clearences to make sure they are within spec. Get a factory manual (Ebay's a good place to look). Get a compression tester and check your compression. You'll see a lot of folks on here talk about the "coil mod". You can read about it here: tinyurl.com/3dsj3x . It's a good, cheap way to put some *umph* back in your spark.

Browse through the filebase section of this site (under the KZ Information menu). Lots of good "how to" stuff in there.

Post edited by: Skyman, at: 2007/09/21 18:46

Well seeing as how I had some relays left over from a remote-start install, I figured to do the coil mod first. Got that done on Saturday then started taking off the carbs. On Sunday I cleaned them all out and despite the fact that they didn't LOOK too dirty, when flushing them out I noticed the discoloration in the cleaner. Just goes to show you can't just look at it and tell how gunked up it might be inside all those channels.
I also noticed one of the floats seemed way off from the other three. Sure enough, you could tell by doing the "service level" check with a clear hose, that it was hardly holding any gas at all.
Finally, I saw that one butterfly valve was about two millimeters off adjustment from the others. I don't have a way to check sync yet, but I figure that there's no way it should be that obvious a difference so I adjusted it by sight for now.

Once I got it all back together, I cranked her up (with an extinguisher at hand) and she cranked over immediatly. A little idle adjustment and she's was purring just fine!
Not bad for my first time working on a bike.

I can honestly say I haven't had this much fun doing maintenance in a long time. For those of you who have car problems that MUST be resolved before going back to work on Monday, rain or snow, you know what I'm talking about.

Next weekend I'll be tackling the charging system since she only runs until the battery is discharged, then I'm stuck with a battery on the charger overnight.

Still,.. I'm 500 percent better off than where I was a week ago!

Welcome!

I am a fellow 300ZX & Kawasaki owner. Nice to have you here on the forum! You'll find lots of useful information here.

Welcome Kraygh!
That H1 will be wild ride, once it's running right. Fast and furious!
Like everyone's said, your carbs probably need a good cleaning. Change the oil charge the battery, and see how she runs. You should be able to do a quick check of each cylinder by pulling the plug wire. On a three-cylinder bike, you'll notice the stumbel in idle, if it doesn't die completely. A compression check will give you a good idea of condition of the valves & rings.
Happy wrenching!