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Discussion Starter #1
I have rejetted my carb since putting on a home made pod kit and slip on exhaust. Sometimes worked great and others would start getting bitchy around 80-90kph. I have had a tried bigger jets leaner and richer mixture with pms screws. Today my father suggested that it might be a problem with the vent hose off the carb that maybe it was partially blocked I removed the little black filter off the hose and viola bike runs like a monster now. Can anyone tell is that a filter or a check valve and does it need to be there?
 

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The black thing is a filter to prevent dirt from getting sucked in. I'm not sure it does much....but mine has always been on there. That vent is very important as you found out. It allows air to move in and out of the float bowls as the fuel drains and re-enters.

You might try zip tying the hose to the upper frame rail. What happens is that you can get turbulence that messes with the vent hose. I haven't had an issue since I hooked it to the frame rail.

https://sites.google.com/site/vstar1100kb/home/repairs/wind-bogging-engine
 

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Would be even better power with a full exhaust rather than just sound. :)
 

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Discussion Starter #5
full exhaust vs. the slip ons I have is very minimal difference in hp. Hard to justify the cost for a 2 or 3 hp gain. I will be straight piping it at some point but if you crunch the numbers not that much of a gain full straight vs. the vance and hines slip ons.
 

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However, if you run a decent intake like a pod set up and/or ever decide to add cams.....those slip-ons will never cut it.

The biggest performance restrictions on the 1100 are the intake and exhaust...fix those and you magically have 10+ more HP. The Virago 1100 (which is the same motor) had 62 HP from the factory compared to 48-52 HP for the V Star depending on who you reference. Guys with pods and full exhaust are showing mid 60's and adding cams and a Dyna 3000 will get you into the low to mid 70's. There aren't many machines out there that you can get a 20-25% gain in HP without dumping thousands into it. That's what makes the V Star 1100 such a freaking awesome bike.

I guess the bottom line is what you want....but it's kind of a package deal. Take away one aspect of the upgrades and everything falls flat.

I know I sure enjoy the extra ponies I've got...:grin:
 

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However, if you run a decent intake like a pod set up and/or ever decide to add cams.....those slip-ons will never cut it.

The biggest performance restrictions on the 1100 are the intake and exhaust...fix those and you magically have 10+ more HP. The Virago 1100 (which is the same motor) had 62 HP from the factory compared to 48-52 HP for the V Star depending on who you reference. Guys with pods and full exhaust are showing mid 60's and adding cams and a Dyna 3000 will get you into the low to mid 70's. There aren't many machines out there that you can get a 20-25% gain in HP without dumping thousands into it. That's what makes the V Star 1100 such a freaking awesome bike.

I guess the bottom line is what you want....but it's kind of a package deal. Take away one aspect of the upgrades and everything falls flat.

I know I sure enjoy the extra ponies I've got...:grin:
i don't how a larger pipe helps if the exhaust port in head isn't enlarged. the two elbows at the very least would need to be bigger to get more air out. those two elbows are really restrictive at those angles.
 

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Discussion Starter #8
However, if you run a decent intake like a pod set up and/or ever decide to add cams.....those slip-ons will never cut it.

The biggest performance restrictions on the 1100 are the intake and exhaust...fix those and you magically have 10+ more HP. The Virago 1100 (which is the same motor) had 62 HP from the factory compared to 48-52 HP for the V Star depending on who you reference. Guys with pods and full exhaust are showing mid 60's and adding cams and a Dyna 3000 will get you into the low to mid 70's. There aren't many machines out there that you can get a 20-25% gain in HP without dumping thousands into it. That's what makes the V Star 1100 such a freaking awesome bike.

I guess the bottom line is what you want....but it's kind of a package deal. Take away one aspect of the upgrades and everything falls flat.

I know I sure enjoy the extra ponies I've got...:grin:
From the charts I found that I think you are actually the one that produced or had a part in it Sick Mick. The jets go from a 147 to a 150 if I upgrade my exhaust. The pod intake and rejetting the carb with the vance and hines slip ons which are pretty much non existant as far as restriction goes. I question how much more I will get with straight pipes.... still intend to do it but the difference I have already seen is amazing with the home made pod kit and rejetting.
 

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i don't how a larger pipe helps if the exhaust port in head isn't enlarged. the two elbows at the very least would need to be bigger to get more air out. those two elbows are really restrictive at those angles.
The exhaust ports are perfectly fine. The restriction is in the head pipes. If you cut one apart you find they are are only about 1 1/4" and maybe a little less in the bends. The motor can push the air with no problem, our dyno pulls show a huge difference in performance when the stock head pipes are replaced.

The 1100 motor has the potential, it just needs to be opened up. I don't know of any other V twin with as much inexpensive latent potential as the 1100. Pods, pipes, cams and Dyna can add 20-25 HP....and still get 45-50 MPG. That makes it awfully fun to play with.
 

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From the charts I found that I think you are actually the one that produced or had a part in it Sick Mick. The jets go from a 147 to a 150 if I upgrade my exhaust. The pod intake and rejetting the carb with the vance and hines slip ons which are pretty much non existant as far as restriction goes. I question how much more I will get with straight pipes.... still intend to do it but the difference I have already seen is amazing with the home made pod kit and rejetting.
It's a noticeable difference, but not as much as adding the pods...that's for sure. But, if your happy...that's all that matters. :grin:
 

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Discussion Starter #11
It's a noticeable difference, but not as much as adding the pods...that's for sure. But, if your happy...that's all that matters. :grin:
I wanted to make my own exhaust but I had originally planned to just take off the slip ons and turn it down 12" further and wrap them. It sounds like if I want to see the full gain I have to go right from the heads...I will have to see if I can make the flange.
 

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Yeah, the turn off the front cylinder is the hard one, but it can be done. Just find somebody with a decent pipe bender. Or you could buy a set of damaged pipes and salvage the elbow. On the rear you can just re-use the factory elbow to make the turn.

On the other hand, I see used aftermarket exhaust for 1100's often. I've had 4 pipe different set ups over the years and none were new. Why spend $500 when $150-$200 will get you what you want....lol. The plus side of that is you can get every single penny back out of them if you decide to make a change.

Also...on the jetting, where you really see it with the full set up of pods, cams, exhaust and dyna. You're up to 157.5 mains in most cases and a very big grin. Without cams, there isn't a huge gain, but it is noticeable.....especially if you're running neck and neck with someone with that set up.
 
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