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Discussion Starter #1
OK, so I decided to forego the DIY carb clean and took my bike into a fairly reputable shop here in town for that purpose.

On top of the carb clean, I discovered that whoever had the bike before put something in the coolant reservoir that they weren't supposed to, so I had to flush that, had to put in a new bladder and other various parts for the carbs, had to get a new front tire, and a few other minor things. Now, the bike runs smoother. The choppiness is gone. When they went into the bike, they somehow broke the return cable, and I have a new return cable and throttle cable on order.

That being said, although the bike runs smoother, it seems to have lost some power. Is this normal for a carb clean? Could the return cable have anything to do with that? Before I took it in, she was actually pretty responsive out of the gate. From zero to 40 or so, I could pretty much take most cars. Now, I have to twist the throttle a lot more to get her going. Is she still getting used to the carbs being cleaned like they were? Will this change once the new cables are installed this week?

It's not horrible, but it's noticeable to me because I remember how she was before.
 

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I experienced a similar problem when I shipped my carbs for a "professional" rebuild. The bike runs great, plugs look normal, but there is a noticeable lack of power. I've done all I know to do and haven't found anything. It's still strong, but not like before the carb work. Wish I could offer some advice but I have none. If you come up with anything, I'd like to know.
 

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Discussion Starter #3
I experienced a similar problem when I shipped my carbs for a "professional" rebuild. The bike runs great, plugs look normal, but there is a noticeable lack of power. I've done all I know to do and haven't found anything. It's still strong, but not like before the carb work. Wish I could offer some advice but I have none. If you come up with anything, I'd like to know.
Did that lack of power stay gone? I assume from the way you said it, it did. Was kinda hoping this would be a "phase" until it works through the system or something, or that it was somehow related to the broken return cable, which hasn't been fixed, yet.
 

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OK, so I decided to forego the DIY carb clean and took my bike into a fairly reputable shop here in town for that purpose.

On top of the carb clean, I discovered that whoever had the bike before put something in the coolant reservoir that they weren't supposed to, so I had to flush that, had to put in a new bladder and other various parts for the carbs, had to get a new front tire, and a few other minor things. Now, the bike runs smoother. The choppiness is gone. When they went into the bike, they somehow broke the return cable, and I have a new return cable and throttle cable on order.

That being said, although the bike runs smoother, it seems to have lost some power. Is this normal for a carb clean? Could the return cable have anything to do with that? Before I took it in, she was actually pretty responsive out of the gate. From zero to 40 or so, I could pretty much take most cars. Now, I have to twist the throttle a lot more to get her going. Is she still getting used to the carbs being cleaned like they were? Will this change once the new cables are installed this week?

It's not horrible, but it's noticeable to me because I remember how she was before.
No it's not normal for a carb clean. If the carbs were cleaned and put back together properly I would say you have a fuel delivery problem. Either a low fuel level in the float bowl or a problem with the float needle valve. Did they adjust the float level to spec? Are the butterfly valves opening fully?
 

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Discussion Starter #5
No it's not normal for a carb clean. If the carbs were cleaned and put back together properly I would say you have a fuel delivery problem. Either a low fuel level in the float bowl or a problem with the float needle valve. Did they adjust the float level to spec? Are the butterfly valves opening fully?
I couldn't accurately answer those questions because I didn't do the work, and I don't know the terminology. Is this something I can check for myself?
 

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I couldn't accurately answer those questions because I didn't do the work, and I don't know the terminology. Is this something I can check for myself?
They should have checked and adjusted the floats when the carbs were off the bike. Same goes for the butterfly valves. You can check to see that the accelerator cable is opening the throttle control plate fully against the stop. That will show you that at least the cable is calling for full throttle.
 

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OK, so I decided to forego the DIY carb clean and took my bike into a fairly reputable shop here in town for that purpose.

On top of the carb clean, I discovered that whoever had the bike before put something in the coolant reservoir that they weren't supposed to, so I had to flush that, had to put in a new bladder and other various parts for the carbs, had to get a new front tire, and a few other minor things. Now, the bike runs smoother. The choppiness is gone. When they went into the bike, they somehow broke the return cable, and I have a new return cable and throttle cable on order.

That being said, although the bike runs smoother, it seems to have lost some power. Is this normal for a carb clean? Could the return cable have anything to do with that? Before I took it in, she was actually pretty responsive out of the gate. From zero to 40 or so, I could pretty much take most cars. Now, I have to twist the throttle a lot more to get her going. Is she still getting used to the carbs being cleaned like they were? Will this change once the new cables are installed this week?

It's not horrible, but it's noticeable to me because I remember how she was before.
I believe the Throttle Return Cable is a tad longer than the Throttle Cable.

Is it possible the shop broke the Throttle Cable, then swapped with Throttle Return Cable..........not knowing they are different lengths ?
Now the bike throttle does not allow true WOT ?
.....just a theory......

WilliamTech
 

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^
Good thought. The accelerator cable is shorter. Worth checking out.
 

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Any difference in cable length can be adjusted. I hooked mine up backwards and couldn't tell
What about the cable guide on the accelerator cable?
 

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Yep I vote for the cable cause if it were fuel bowl related, you'd be getting stutters and bucks. Now you can certainly be getting less fuel through the lines but I know exactly what you mean. The bike feels soft and silky instead of quick and hard...er ok Doc, settle down now.
 

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What about the cable guide on the accelerator cable?
That's what made me reverse them. However, the decel cable can hook up to the accel side, and ALL the slack can be adjusted out. It doesn't matter what kind of cable it is - if it's not slacked, it'll perform identical.

If I'm wrong, someone tell me what I'm missing?
 

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That's what made me reverse them. However, the decel cable can hook up to the accel side, and ALL the slack can be adjusted out. It doesn't matter what kind of cable it is - if it's not slacked, it'll perform identical.

If I'm wrong, someone tell me what I'm missing?

However, the decel cable can hook up to the accel side,


Agreed

and ALL the slack can be adjusted out.


I would assume

It doesn't matter what kind of cable it is - if it's not slacked, it'll perform identical.

True

Is his cable adjusted properly ?

WilliamTech
 

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yes if its lean you will lose power if its rich you will lose i played with my mix screws for 3 hours to get them right i have learned that the 2.5 truns out on the screws is just a starting point i have mine set at 2 3/4 turn and its runs great im guessing its just like a holley carb for a car u have to tune them to your motor so turn them all the way in (not tight) then back em out 2.5 turns and then tune as needed
 

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As I understand it, the mixture screws only affect the primary circuit and through the low to mid rpm range the carbs are on the intermediate jets. It's only when we get into the high mid to upper throttle setting that we are using the main jets. Others with more knowledge please weigh in. I've checked to make sure the throttle is opening like it should and it is. I've checked for vacuum leaks and all seems good. I've done the carb sync twice and that's good. The plugs look normal. When I first reinstalled the carbs the front float was sticking and pouring gas into the fron cylinder. Could that have caused a problem? The guy at the carb shop says everything is at factory specs. I don't know why the bike has lost power but it definitely has. The only other thing I've noticed since the carb work is there is a slight pulse at idle whereas before the idle was much smoother. Sorry, not trying to hijack the thread, but just passing along info on a similar problem.

I determine which cable is which by observing which one retracts into the sheath when the throttle is turned. The one that retracts is the accel cable, the one that extends is the decel cable.
 

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Discussion Starter #17
I believe the Throttle Return Cable is a tad longer than the Throttle Cable.

Is it possible the shop broke the Throttle Cable, then swapped with Throttle Return Cable..........not knowing they are different lengths ?
Now the bike throttle does not allow true WOT ?
.....just a theory......

WilliamTech
I was thinking something along these lines, too. The bike seems to run fine. The only problem with this theory, though, is something that happened yesterday. I had her on the turnpike, and not only was she having trouble accelerating at one point, but she was acting like she was running out of fuel, and was decelerating. I had to pull her off the road, kick her down into a lower gear, and that seemed to get her going again. I had to do that twice.

Now, that being said. I immediately put new fuel in it at the nearest station, and they had been running that AMSOIL stuff in the tank that was doing that.

Again, with a new petcock as part of the service (forgot to mention that, before) there are so many variables, I wouldn't even know where to start.
 

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Discussion Starter #18
Yep I vote for the cable cause if it were fuel bowl related, you'd be getting stutters and bucks. Now you can certainly be getting less fuel through the lines but I know exactly what you mean. The bike feels soft and silky instead of quick and hard...er ok Doc, settle down now.
Goofy...that's EXACTLY it. Runs nice, smooth, just feels like I'm on a Rebel rather than a Vulcan.
 

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Discussion Starter #19
Also, did they replace anything internal in the carbs?

What about the mix screw? If they leaned it out wouldn't it lose power?
Um, float needles, bladder...a couple of other various O-rings, I think.
 
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