TOPIC:

Sounds like they're not switched.
Steve

I've ordered a set of replacement throttle cables to remove the slacky cable as a source of weird idling.

So since everything else seems okay, my theory now is that when I do get it to run on new spark plugs, I should tune and sync the carbs right away. I'm thinking that because it does start and then it runs rich-ish, and I'm not riding it at all, I get the plugs all sooty and they never get a chance to get hot enough to get cleaned up. Then I let the bike sit over night or for a couple of days before trying again and by then the carbon is built up?

If I can tune it right away and get the mix right and maybe take it around the block, then finally my spark plugs might stop fouling? Just a theory.

One thing I didn't do yet is check the floats. I'm going to get some tubing and measure the floats while I wait for the cables to come in.

Did you do the clear tube test?
Steve

SWest wrote: Did you do the clear tube test?
Steve

That's the one check I haven't done yet on the carbs, the float heights. I'll grab some tube today and see how that goes.

Now that the weather is nice again, I've resumed work on this project

I drained the fuel before I stored the carbs. I attempted doing the float test before storage but by then it was cold and I was having a hard time setting things up, so I decided to wait.

I made a carb holder out of some tubing and it seems to work okay (better than trying to prop the carbs up with jack stands on either side smh). I'm using the clear tube method and I did the first carb so far, I'll do the other three in the morning.



As per my manual, I am measuring the distance from the base of the carb to the height of the fuel in the tube. I am checking that the distance is between 2.5 mm and 4.5 mm. I believe since I stored the carbs dry, and its only been a few months, I don't have to bother opening the carbs up again and cleaning right? I would like to avoid this if possible but let me know what you guys think.

After the above is done, I will replace 3 of the carb boots which are leaky. I found some used ones and are better than mine so I will be swapping them to fix any air leak I might have.

At that point, I think I've done all the steps to get things going. If there's something else that I should check/do please let me know. I have a new set of spark plugs that I will use.

You may want to lower the height of the fuel tank down to a level that is closer to the level that it would be at when mounted on the bike. Otherwise the fuel pressure will be greater than normal, and that may lead to other issues.

Also, if at all possible I highly recommend buying NEW carb holders; not used. Old (used) ones will leak - soon if not immediately. New ones will last a very long time. Ed

Thanks Ed. Yeah unfortunately Z1 is out of stock so I thought the used ones were better than using my worn ones. Turns out it isn't the right one for my carbs anyway. I didn't realize when I picked it up that there was no vacuum port on the boot. So I'll have to source some replacement ones out now.

I think today was mostly a success...

- I replaced both throttle cables, cuts off nice and snappy now.
- I verified all float heights were in spec.
- Before the first start up, I had the Morgan Carbtune hooked up and carb tops removed so I could make adjustments if needed.
- Did NOT replace carb boots.

Started up like before, smoky exhaust and high revs, and the Carbtune gauge showed very out of sync carbs. I played and tweaked with them until they were all even. After a few blips I checked again and made small tweaks. Exhaust finally comes out clear!! First time I've been able to get this state, so I'm happy with that. I can get the idle to be pretty stable at around 1.8k-2k as well.

Current situation:

1) If I start to close the choke (it was fully open when starting) the engine starts to rev up. It quickly goes from 2k to 5k and then hovers there. If i open the choke slightly, it drops the idle a little. Playing with the idle adjuster doesn't help.

2) The throttle is sensitive and shoots up to 5-6k. Once it gets to this level, even if I let go of the throttle and back off the idle screw, the revs stay high. I tried resetting the mix screws but end result was the same: It sits at 2.5 turns out.

I read that both the above problems might have to do with a lean issue. Obviously my boots may be a source. I tried spraying some starter fluid on the boots to test this out... didn't seem to do anything though. The other possibility I guess is a dirty jet?

I think overall today was good because I could get her to start up multiple times which I couldn't before. And the carbs are height adjusted and synced, no white or black smoke from exhaust. Now I just need to figure out this weird idle and throttle issue. What do you guys think?

Sounds like your idle RPM is high, should be around 1000. A little more or less as each bike is slightly different. Choke sounds like it’s correct. I start my bike on full choke and quickly shut It down and it will build rpm as I’m closing it down till I get close to off and then I feather it to get good strong idle without it to high in the rpm range.

Do you air pilot or fuel pilot screws. Air would be on the air box side and fuel would be on the bottom of the bowl closest to the “carb boots”

Unfortunate you didn’t clean the carbs while you had them off, really hard to diagnose without knowing the carbs are correct.

Mikaw wrote: Sounds like your idle RPM is high, should be around 1000. A little more or less as each bike is slightly different. Choke sounds like it’s correct. I start my bike on full choke and quickly shut It down and it will build rpm as I’m closing it down till I get close to off and then I feather it to get good strong idle without it to high in the rpm range.

Do you air pilot or fuel pilot screws. Air would be on the air box side and fuel would be on the bottom of the bowl closest to the “carb boots”

Unfortunate you didn’t clean the carbs while you had them off, really hard to diagnose without knowing the carbs are correct.

Interesting, I'll try dropping the choke faster next time.

I have fuel pilot screws.

I did do a full clean and replaced gaskets last year when I first started working on it. When I removed the bowl while doing the float adjustments I noticed it was still very clean. But I guess it's possible one of my jets are still blocked?

I am by far a carburetor expert. I have only rebuilt 3 sets but every thread I have read on this forum mentions the only correct way to do it is to ungang and completely disassembled. Even that method isn’t foolproof but gives you a much higher success rate. You may just have a bad O-Ring in the choke enricher circuit

I opened up the carbs again last night. I cleaned the jets again but this time I replaced the float needle, fuel mix screw, and the slide needle on each carb. I had these parts as part of the rebuild kit but I tried to use what was already on the bike. Decided to just swap in the new ones hoping it helps. I was really thorough on my last clean, everything still looks good in there.

My Kawi dealer ended up showing stock for OEM boots (part numbers 16065-046 : left, 16065-047 : right) but they are so damn pricey now. Each boot is $44 CAD! It's super over priced but I can't do anything about it, not in stock anywhere else and it's an OEM part, so I'll just grab that.

Parts will come in next week, stay tuned.

I don't have a 650 so can't be of much help there I guess. If you can find new OEM carb holders for almost any reasonable price buy them. OEM is the only way to go with these things to make sure they don't leak or go kaput in the near future. I am a bit confused on your problem description though. You say you start it up cold with the choke full on and it revs high which it should. On mine I immediately start pushing the choke lever off to get the idle to come down. I don't want or need it running at 3500+ RPM's cold. I try to get the choke off (down) to about 2,000 RPM's for initial warmup. After as minute or so I push the choke off and drop RPM to about 1500. After another minute or so the engine is warm and I push the choke lever completely off and the engine drops to normal idle of about 1100 RPM. You can't really adjust anything when the choke is on in the slightest as the starting circuit is carrying the load at that point so to speak. Others that own 650's may chime in with different thoughts on this.

Rick H.