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The subject says it all. I just ordered a set of V/H Cruzers for my 06. I see that some jet kits require drilling? drilling what?, and some kits dont. Do the carbs have to be removed and re-calibrated?. I dont want to get in over my head here.

Thanks
 

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unless you remove the ears (the intake system), you don't have to re-jet
 

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Now, I appreciate everyone here and the fact that they haven't rejetted their carbs after installing V&H pipes w/o earshave, but I'm having a tough time swallowing this one. I've done a lot of tuning of carbs on performance Mustangs as well as EFI tuning via software on the more modern Stangs - the basic principles of tuning that I've become so familiar with should still apply to the little 749cc V-twin motor in our Vulcans. After I installed V&H pipes on my '02, I can tell it's a little bit low on power. When it's fully warmed up, it does feel like it's running slightly lean. And I mean slightly, as in so slight that the plugs aren't showing an excessively lean condition or anything, which would also explain why it runs pretty decently. However, in order to squeeze maximum power out of the exhaust upgrade, it's definitely going to be necessary to enrichen the mixture in the midrange and top end. The idle seems like it could stay as is. If I could devise a little device to hook my wideband O2 sensor to the exhaust pipes, I might be able to figure out exactly how lean it is with the A/F reading.

I dunno... I just expected to gain power from the pipes, not lose some.
 

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Yeah, everything I've heard is that when you degoat, you lose low end torque. My understanding is that the goat acts like tuned headers. I have not degoated because of this. We're only running like 40 something rear wheel HP; any less and I could have saved money and gotten a smaller bike. So re-jetting might be the answer.
 

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yes, you are right. from factory, even with stock pipes we are running lean. Also IIRC i think we are on the 3rd to hottest plug availiable for our plug size, so you wont show as much lean mixture on the plugs. If you enrichen the mixture, you'll have to mess with the timing and move to a differnent set of plugs. I got in touch with MSD, and they said i would have to modify one of their timing plates to fit so i could put in one of their ignition systems. Havent decided if its the way for me, but might be an option for you. I firmly believe we can get much more out of this 749cc engine, but the parts arent there. cams, and tuned pipes and ignition upgrades could prove interesting....if you have the cash.
 

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and the Adventure Cycle
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IMO, if you change the exhaust, to get optimum performance, carb tuning should be done, although it might not need to be done.

My bike had been degoated and aftermarket pipes (possibly Cobra's, but I'm not sure) added by the previous owner. I have no clue if any tweaking to the carbs was done or not, and they haven't given my any troubles yet, so I haven't messed with them.

Good luck Rubline and post some pics when ya get the pipes on.
 

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I'm getting mixed responses regarding Dynojet supplying jets for our carbs. Some local shops are telling me that they have Dynojet brand recal kits for the VN750, while others say no. Factory Pro obviously has some recal kits for us. Any other manufacturers of jet kits out there?
 

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cegodsey said:
Yeah, everything I've heard is that when you degoat, you lose low end torque. My understanding is that the goat acts like tuned headers. I have not degoated because of this. We're only running like 40 something rear wheel HP; any less and I could have saved money and gotten a smaller bike. So re-jetting might be the answer.
I believe our rwhp is higher than 40's. Flywheel is like 65 hp, rear wheel is like 59 hp. But, whether you degoat, or put on any other pipe that is one per cylinder, you'll lose performance. The stock system allows each cylinder to see two mufflers, less restriction. Either degoat or V&H's will run one cylinder into one muffler. I have degoated and am in the process of fabricating an "H" pipe for it. I think this will restore the factory power, yet get rid of the midchamber that generates so much heat exactly where we don't want it.

Even 8 cylinder cars benefit greatly from an "H" pipe. I believe more power will be had from the "H" pipe than rejetting.

I will post up my findings when the "H" pipe is in.
 

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Here's the specs from the dyno test on a bike with an ear shave:

> 45.75 HP
> 33.83 torque

These numbers are rear wheel horse power. Stock has gotta be less, right?

Here's the thread:
http://autos.groups.yahoo.com/group/VN750/message/134087

Assuming you have the membership to this forum.
 
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