Help with a V Star 1100

[ToyOdie]

A buddy asked me to look at his V-Star 1100. It had been at some fly by night mechanic for 3 months. It originally went in for a fuel leak (float sticking) and a new rear tire. By the time he got it back it had a starter clutch upgrade, #1 intake valve replaced, rear tire replaced, a few odds and ends and still didn't run right. I pulled the carbs and found that he hadn't cleaned them even though he charged him for it. I cleaned and replaced both needle and seats and the bowl seals. He had opened the carbs because he used RTV (non-fuel resistant) to seal the old bowl seals. I found the valves on #1 way out of adjustment, so I fixed that. Replaced the missing nuts and bolts that were never reinstalled on numerous parts. After I got it all back together I synced the carbs and played with the mixture to get it running what I thought was perfect. Then I installed the air filter and derby and took it for another ride. Everything seemed great until I tried to accelerate hard. The engine would start to rev and then would die. If I add throttle slowly the bike ran great. I went back home to troubleshoot. Up to this point all the engine running was with out the air filter and derby so I could get to the carbs. So I took the air filter off and took the bike up the street. It worked great. I put the air filter back on and the problem came back. Problem solved, or so I thought. I told my buddy what I had found and he said he would buy a K&N filter. I gave the bike back to him and he put the new filter in. The problem has not gone away. As long as the filter and derby are installed you can't accelerate quickly with quick throttle movement. He said he removed the foam pre-filter and that made no difference. It sound to me like somewhere in the derby/filter there is a restriction in the air flow. Anyone have any other ideas?

[bongobobny]

Vacuum advance issue???

[djh3]

I'm not familiar what year they made these or anything so I will guess it is electronic ignition and carb. How does the derby mount? Possibly is an attaching part for it pushing the choke plate or restricting? Is there a hose or housing that connects to the derby? Sometimes they look like a cover but yet then connect to air hoses that go under the seat or tank,like the RSV. If so maybe a restriction back up stream? Or is it like a sportster and just open behind it? Are you sure its the correct air cleaner and filter assy for the bike?Just throwing ideas at ya.

[ToyOdie]

Yes it is a 2007 with electronic ignition and carburetors. There is an air box just like the 96 Royal star tour classic mounted under the tank. There is a duct that comes from the airbox to the back of the derby. Inside the derby there's a foam pre-filter and now a K & N filter. I have had it all off and cannot see any place where there is an obstruction. I'm just trying to figure out why it runs perfectly without the air filter and will not accelerate quickly with the air filter installed.

[cowpuc]

Just from the hip having never worked on a V-Star 1100 but having worked on a few Virago's and others... May wanna take a peek at the carb diaphrams and vacuum lines.. Also, If I had been told all that work had been done and then discovered that the guy had cheated my buddy on a carb job, I would begin with the basics and check his other work.. Do a quick compression test just to check the mechanics skills on valve work, check the vacuum lines for proper placement and so on.

Also,, if that model still has the Vacuum operated fuel petcock you might wanna check its operation.. If it does, pull the vacuum line off the petcock and see if there is fuel in it - if so ya got a bad diaphram in the petcock..

[midnightventure]

The fly by night didn't put bigger jets in it did he?

[ToyOdie]

I don't think the jets were changed. All the vacuum lines are attached. When I set the valve clearance I verified the cam timing marks were set properly. The bike runs like a banshee without the air filter. It's like a crotch rocket with saddle bags. I just can't figure out why it can't get enough air with the filter installed.

[cowpuc]

Is it possible that the new filter is a oil dampened filter that he has too much oil on??

[MikeWa]

Try installing the air filter housing without the filter and see what happens.

 

Mike

[ToyOdie]

I returned the bike to the owner before I posted the help request. I have been relaying the fixes that have been posted. I finally started looking at the parts breakdown and found no pre-filter is listed. I had him remove the pre-filter that the previous owner or the fly-by-night mechanic installed. Problem solved. Thanks for the help.

[dacheedah]

Yep another reason to learn to wrench.

[djh3]

So what was the "pre-filter" Just a foam wrap around the filter? Or was it something that was separate?

[ToyOdie]

It was a two stage foam filter stuffed in the back of the filter housing. You could see it through the back of the derby housing when the filter was removed. It actually looked like it belonged there until it was removed. Then you could see it had been cut from a larger piece.