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Discussion Starter #1
I just had my carbs overhauled at the dealer (too much work, not enough time). Expensive, but hey...I want to ride. I picked up the bike this morning.

I noticed several things are different:
1. Rougher idle - not terribly rough, but not the smooth idle I had a year ago. After temp gauge moved into the operating range, I removed all choke and the bike died. Perhaps idle was set too low, so I raised the idle and it doesn't die now, but not as smooth as I would like.
2. Choke now appears to work as it should. Full choke, no throttle and the bike starts. I reduce choke as it warms up and reducing the choke drops RPM. That's good.
3. I have to roll the throttle back quite a bit to shift or the engine RPM climbs when I disengage the cluth. I didn't have to do that before. Is this "normal" to have to roll the throttle to idle before shifting?
4. I get the occasional backfire when downshifting and letting the engine brake the bike.

Thanks in advance for your expertise.

Texas Cruiser
 

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Now what
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Texas Cruiser said:
I just had my carbs overhauled at the dealer (too much work, not enough time). Expensive, but hey...I want to ride. I picked up the bike this morning.

I noticed several things are different:
1. Rougher idle - not terribly rough, but not the smooth idle I had a year ago. After temp gauge moved into the operating range, I removed all choke and the bike died. Perhaps idle was set too low, so I raised the idle and it doesn't die now, but not as smooth as I would like.
2. Choke now appears to work as it should. Full choke, no throttle and the bike starts. I reduce choke as it warms up and reducing the choke drops RPM. That's good.
3. I have to roll the throttle back quite a bit to shift or the engine RPM climbs when I disengage the cluth. I didn't have to do that before. Is this "normal" to have to roll the throttle to idle before shifting?
4. I get the occasional backfire when downshifting and letting the engine brake the bike.

Thanks in advance for your expertise.

Texas Cruiser
For the idle, I'd run a healthy dose of Seafoam through it. They might have knocked some junk loose and didn't get it all out.

The bike should run fine with the idle set at 1100 rpm when the bike's warmed up.

If you have the idle set too high, I can see where it would act wierd when you shift. Reset the idle.

Maybe the carbs need to be synched. It should have been done after they put the carbs in but you never know.

If it doesn't run right with the idle set correctly and after running some Seafoam through it, you should take it back and have them look it over again.
 

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you may also wanna check the cable adjustments on the choke to make sure when you have it off, it is really off, and also make sure that the throttle isnt too tight. But to be honest, the idle issue sounds like they messed up shimming or something.

also the popping is somewhat normal. before your carbs were gunked some. so at idle and decel, you run lean, so no pop, but now it may run a lil rich (which is normal).

i suggest a normal check out on the carbs. this includes seafoam, syncing, draining the bowls, check the boots (yes makes a difference), check the cable adjustments, after all that, then adjust the idle. also i would check the air filters, when was the last time they were cleaned? I am in dallas and drive by construction, so i clean mine every 6-9k miles.
 

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Man good are getting harder and harder to find.You would think with the training they get at the service schools that Im sure that they send them to that they could make your bike run like new.I used to be a small engine mechanic and that motor I worked on ran like it was brand new I just dont understand.........
 

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and the Adventure Cycle
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I don't know if I'd do anything yet, except to take the bike back and tell them that it's not right. And, you don't expect to be charged to have them fix their mistake.
The expense of having a (authorized?) dealer do it should mean it's done right, the first time.
 

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hyperbuzzin said:
I don't know if I'd do anything yet, except to take the bike back and tell them that it's not right. And, you don't expect to be charged to have them fix their mistake.
The expense of having a (authorized?) dealer do it should mean it's done right, the first time.
I agree
 

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rnewell said:

The shifting problem does remind me of the idle. I've had that problem before, and yeah, it's a pain. Drop the idle and it dies. I just cranked on the air/idle mixture screws until it lined out. That was, of course, a SOHC4 Honda, and not the Vulcan.

Take it back and complain. If you don't, it only gives more credit to the mechanic. I was proud of the lack of returns I got, which gave me a pretty good reputation, but I couldn't help but wonder how many people took their stuff to other mechanics after I was done.

I know it happened a couple times, but those people couldn't understand when I told them that Craftsman power equipment is garbage to begin with, and not worth repair.
 

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Once Banned
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And that would be power equipment, not tools. Although I did go through several 13mm sockets taking off the head bolts of my last car. But they were replaced for free.
 

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Engine not wanting to throttle down during shifts could be badly adjusted throttle cables, or vacuum leaks. Rougn idle could be vacuum leaks and/or carbs out of sync. I'd be back there as soon as they open!
 

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*Engine not wanting to throttle down during shifts could be badly adjusted throttle cables, or vacuum leaks. *

Fergy's got a good point. They may have misrouted the cables when they reinstalled the carbs. It's easy to get them to bind.
 

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You know we talk alot about dealers on this forum, not knowing much about our bikes and one of my buddys has a harley sportster that he's had for about 3 years. About 7-8 months ago it started running bad, spitting and backfiring when he'd roll on the throttle after it warmed up. He's in Florida now and it happened just after he moved there in the spring. He's had 3 different harley shops work on the bike and they've gone from telling him it was altitude related (moving from Texas to Florida--around here the average is around 850 above sea level) to regulator and stator problems. They even put on a new high performance carb set. Nothing they have done has even effected the problem! $1100 dollars later, he found out through his dad that he had a distant cousin in Georgia that has been a harley mechanic for 15 years, so he calls him up and he tells him what's been going on, and he says, oh, it's your map sensor that's gone bad. So he goes and buys a new one for $47 and puts it on and just like that, it's fixed! Well, I shouldn't say it's fixed, he's having to go back to the stock jets that came with the new carbs cause one of the shops rejetted the carbs trying to get it to lean out as it was blackening the plugs in 15 minutes! Anyway, I tried to tell him that he wasn't alone but that didn't seem to calm him much!

Good help is hard to find!
 

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All this stuff really reflects badly on the industry
 

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Discussion Starter #15
Thanks for all the insight.

The idle was set way too low...I had to raise it to about 900 to get it to idle after the engine was warm. I think I'll make a phone call to the dealer...I paid $400 to have them overhauled, and I would expect everything to be set to specs. Clearly the idle wasn't...I wonder what other corners were "cut".
 

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900? You had to raise it to 900? What was it set on? I think specs are 1000 or 1100. Mine sits somewhere around 1100.
 

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Discussion Starter #18
The idle was very low...I don't know how low because it wouldn't run at idle. I believe the idle spec is 1,100. I'll verify that or adjust today. I have not resolved the issue with rolling back the throttle before changing gears. I am still looking for my maintenance manual before diving into this. I hate it when I can't find things. Grrrrr.
 

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If it doesn't run right, take it back first thing when they open again. You paid good money to have it fixed right the first time. You shouldn't have to dig through your maintenance manual to find specs. That's their job. It's one thing to do the work yourself and foul it up, it's another to have a supposed professional foul it up and not take responsibility. You said yourself, you don't have the time or expertise to do the job and you hired them to do it. Hold them to the standard that they should strive for!! If they won't do quality work, or stand behind their work, make it known throughout the community. Lack of business will wake them up or put them under.
 

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Discussion Starter #20
Thought you guys would like to hear the update and resolution to my carb rebuild saga.

I took it back to the dealer who overhauled the carbs. No argument, no BS. He took the bike and said he'd fix it.

I picked it up Sat before New Years. No charge. Fergy gets the gold star! Vacuum leak. Starts, idles and accellerates through the throttle range just fine now. I made a minor tweak to idle and the decellerator cable and I'm back on the road again!

A big S. Texas gracias to those who commented and led me down the right path.

Texas Cruiser
 
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