Power loss

[racinnuts]

I bought washers to shim the carb, so I will clean the carb and adjust the valves when I install the washer. I have checked the electrial connections, wires, etc. and installed a new spark plug and battery but still have the problem ocassionally. I forgot to mention that this normaly happens in the morning on the way to work. Maybe my GZ is trying to tell me something!

Thanks for the input,
racinnuts

[Easy Rider]

Originally Posted by 1Rogue

on larger roads with a little higher speeds. I did not get this problem at the lower speeds. It is only when I get in the area of 45-55 that it happens. I was trying to pay more attention tonight when I was riding and it did seem to do it some when I was holding speed and not really throttling up.

This sounds like the classic case of plugged gas cap vent. Vacume in the tank cuts gas flow down to a trickle and doesn't keep enough in the float bowl to support sustained high speeds. Also could be improperly set float, gunk in needle valve or partially plugged screen(s) in the petcock or tank.

Good luck!

[1Rogue]

Originally Posted by Easy Rider

This sounds like the classic case of plugged gas cap vent.

Well I got and used the Seafoam and figured I start with that. Any tips on how to check the gas cap to see if it is the culprit. If these don't work I guess I head for the carb and the tank workings.

Thanks for all the great info everyone. I'll keep ya posted.

Oh, yea - if I find it is the cap. Is there a way to clear it, or do I have to buy another one.

[racinnuts]

You should be able to hear a sucking sound and fill the vaccum when you take the gas cap off if the vent is plugged. I can hear my cap venting after my bike has been sitting on a hot day and I lean it from side to side if the tank is pretty full.

[1Rogue]

Originally Posted by Easy Rider

This sounds like the classic case of plugged gas cap vent. Vacume in the tank cuts gas flow down to a trickle and doesn't keep enough in the float bowl to support sustained high speeds.

I'm about 3/4 through a tank of gas with Seafoam. I have seen no noticeable difference. I thought I would address the plugged fuel cap vents next. It doesn't suck air when it is parked and I open it, but being as it only happens at upper speeds I don't know how to test it. Is there a way to clean them out, or do I have to buy a new one. I really hope it is not the latter, that looks like about $60-$70.

[Easy Rider]

Originally Posted by Easy Rider

This sounds like the classic case of plugged gas cap vent. Vacume in the tank cuts gas flow down to a trickle and doesn't keep enough in the float bowl to support sustained high speeds.

Originally Posted by 1Rogue

I'm about 3/4 through a tank of gas with Seafoam. I have seen no noticeable difference. I thought I would address the plugged fuel cap vents next. It doesn't suck air when it is parked and I open it, but being as it only happens at upper speeds I don't know how to test it. Is there a way to clean them out, or do I have to buy a new one. I really hope it is not the latter, that looks like about $60-$70.

Just went out and looked at my cap. It's a pain in the ass compared to the "flip caps" on most other bikes I've had. It doesn't seal until it is completely closed SO.......If you have an extra key, I would think that with 1/2 tank or less you should be able to leave it open 1/4-1/2 inch without fear of it coming out (mine is very tight until I get it all the way out) or any appreciable splashing.....if you ride mostly straight up with no sudden starts or stops. It looks like it comes apart with 2 screws but I decided not to look inside mine!

If that turns out to be the problem, I think I'd soak the whole cap for a while in some carb cleaner before dis-assembly or replacement.

If that is NOT the problem, the next thing I'd do is check for a vacume leak in the line going to the petcock, then check the screens. Think I heard they are on the fuel pickup inside the tank at the top of the petcock. Next would be float levels.


Good luck!

[1Rogue]

Originally Posted by Easy Rider

If that is NOT the problem, the next thing I'd do is check for a vacume leak in the line going to the petcock, then check the screens. Think I heard they are on the fuel pickup inside the tank at the top of the petcock. Next would be float levels.

Well, it isn't the vents in the cap. Just got back from trying your leave it open suggestion. I even had it completely off on a couple of the long straight aways. It still was skipping out. I'm going to hit the manual and see where the line the petcock is you suggested to check. I'm guessing I am going to go ahead and break the tank down and check the screen and all inside.

[Easy Rider]

Originally Posted by 1Rogue

Well, it isn't the vents in the cap. Just got back from trying your leave it open suggestion. I even had it completely off on a couple of the long straight aways. It still was skipping out. I'm going to hit the manual and see where the line the petcock is you suggested to check. I'm guessing I am going to go ahead and break the tank down and check the screen and all inside.

Alas, you are rapidly eliminating the easy things.
If the fuel flow is not restricted, then it would seem that you are left with a low float level or an intermittant (heat related?) electrical problem.
Good luck. Sounds like you'll need it! :sad:

[1Rogue]

Originally Posted by Easy Rider

Alas, you are rapidly eliminating the easy things.
If the fuel flow is not restricted, then it would seem that you are left with a low float level or an intermittant (heat related?) electrical problem.
Good luck. Sounds like you'll need it! :sad:

Two questions here. - Is a special tool required to check the float level or is there a way to do it without dishing out cash for a special tool? Also, is breaking down the carb difficult? (Remember your dealing with a newb here.)
I think I am going go for broke. I should be getting the 16t sprocket in today as well as the extra washer to do the shim. Since the tank is off and I'll be going into the carb anyway, I figure I may as well break it down and clean it.

I got this bike hoping it would be a good beginners way to learn how to work on them. But not a crash course! :mad:

[jonathan180iq]

If you're gonna do this, don't let the carb intimidate you.
If you don't take off parts that shouldn't be taken off, you'll be fine.

I have one favor to ask. Since you are already torn down, would you mind measuring the inlet diameter and total circumferance of the carb intake? I haven't gotten there and probably won't for some time.




You're watching part number 20 in this pic.
Here is a link that I used a looooooong time ago.

http://771doug.netfirms.com/float.html

If you don't feel confident with this procedure or with the help of the service manual, I'd suggest takin' it in.

Needless to say, carbs are pretty important in the function of the bike. You don't want to screw something up.