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Discussion Starter · #1 ·
I've having a custom exhaust fabbed up on my 865 bonnie and need some advice on what to Rejet it to. It's coming out sick. Just waiting for it to get back from the powdercoater.

Here's some info.

1. I'm using Norton Commando pea-shooter silencers with custom headers and no cross over.

2. Stock box with snorkel and restrictor plate removed.

3. AI removed.

what do you think I need to rejet to? The silencers are pretty high flow from the looks of it.

thanks for the help!
 

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first of all, no help until we get pics.

Just kidding, but we want to see some pics.

hmm, 865, you already have the Thruxton needles, so I'd start with 1 shim on each needle and maybe 150 mains.

If you want to try the stock pilots, I'd try 2.5-3 turns out, if you want to go up a size I'd try 1-1.25 turns out on the idle mix screw.

I have predators, and run 155 mains, I think I could stand to go up a size. If you start with 150 mains you'll at least be in the ballpark.

Can't wait to see that exhaust. I hope it's getting some kind of high-heat coating, and I hope that coating is black...
 

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Discussion Starter · #4 ·
Thanks, Sweat. I knew I could count on you. Hopefully Rodburner will chime in too.

Of course buddy, I'll post pics as soon as I get it back and the custom alum heat shield made. It's going to look like the Paul Smart's Imola racer with staggard pipes.

It's getting ceramic coated satin black. ;)

I want to keep the stock airbox just so I don't get into anything too involved with adjustments. 130 mains enough you think?
 

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Discussion Starter · #6 ·
cool. gotcha...
I might have to give Brent a call at newbonneville and order a NARK.
 

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Discussion Starter · #8 ·
nice! thanks again, man.
hey, do you happen to know where I can get exhaust manifold flanges?

Since my guy was doing the exhaust for me using my stock header flanges, I thought I'd try to find another 2 sets of flanges so I can run my stock mufflers if I wanted, and to make a set of drag pipes.
 

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Discussion Starter · #10 ·
yeah, we thought we'd be able to fab some flanges, but they're actually have an offset bulb inside that angles the flange into the manifold. It's not flat on the side that fits to the manifold. they look as if they are cast with the fins and all and welded to the headers.

I'm going to ask him again to see what he can do...
 

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I guess you're not wanting to sacrifice your stock pipes?

I'd contact bonneville performance, they have their own full exhaust so I'd imagine they could hook you up with some flanges. Bill Gately is very helpful. He's the owner, and operates his own bonneville flat track team. Dude knows more about these motors than anyone, except maybe Jojje.
 

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Mase,

I'm not sure if the difference in crank layout (360' V 270') matters, but with de-baffled stock pipes and the same airbox mods as you, plus opened out inlet plate: modified Scrambler airbox I was on 130 mains, Thruxton needles with two shims. That's with 'seat of the pants' dyno figures.

I'm now on 140s with K&N pods (on a real dyno next week) so the 130s are yours free if you pm me your address.

[ This message was edited by: johnyC on 2007-01-16 04:11 ]
 

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Discussion Starter · #13 ·
thanks JohnyC!

PM sent.
 

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Mase,

I believe the others have better suggestions on the main jets and needles than I would. However, on the pilot jets, I would recommend trying 45's. When I ran header pipes with no crossover on my 790, I had to run 45 pilot jets. When I put the headers with crossover back on, I had to take out the 45 pilot jets to get it to run properly at the low end. FWIW, I really believe these motors run better throughout the rpm range with headers without crossovers. Some day I will purchase a set of quality made headers without the crossover...the ones I had were pretty poor quality, but the performance difference was noticeable. :-D

Larry
 

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Discussion Starter · #15 ·
On 2007-01-16 01:39, sweatmachine wrote:
I guess you're not wanting to sacrifice your stock pipes?

I'd contact bonneville performance, they have their own full exhaust so I'd imagine they could hook you up with some flanges. Bill Gately is very helpful. He's the owner, and operates his own bonneville flat track team. Dude knows more about these motors than anyone, except maybe Jojje.
Stock pipes were sacrficed in this project.I just want to get a couple more sets to make some alternatives in case the wife rides with me and doesn't want to scorch her leg.

Good call on bonnie performance. I'll give them a shout!
 

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Discussion Starter · #16 ·
On 2007-01-16 20:24, RedBird wrote:
FWIW, I really believe these motors run better throughout the rpm range with headers without crossovers. Some day I will purchase a set of quality made headers without the crossover...the ones I had were pretty poor quality, but the performance difference was noticeable. :-D

Larry
Nice! Thanks for the input. I'm excited to see how it runs without the cross over. I know there has been debate about wether or not the motor runs better or not with the crossover. we'll see...

I might just take it into the dealer and see if I can get an opinion on my setup.
JonhyC hooked me up with 130s and I'll add 45 pilots and see how close I am.

NOW, I'm wondering if the uneven header length will cause any issues....

I'll have the bike back by the end of the week, so I'll have pics to post up by then.
 

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NOW, I'm wondering if the uneven header length will cause any issues.... >>>
Mase, for your unique application, will be better for you to jet your bike on a Dyno with gas analizer, one cylinder at the time, because dynos has a single gas analizer and you have not a crossover.I'm almost sure that each carb will have different jetting.
An air box elimination kit, will be a must, with such a frew flow exhaust system.
I hope this help.
 

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No cross-over tube means a couple things, louder, and potentially a better chance to dial in the individual carbs. The engine may lack linear power via it's compromised mid-range, but she's gonna scoot and respond well to wide open throttle!

I could only venture a guess at jetting, and I'm thinking 42 pilots and 130+ mains with a K&N or UNI. A shim is the very last thing you do IF she's tripping over herself between on-throttle & off-throttle.

The pipes will likely look REAL nice and sound even sweeter!
:cool:
 

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Discussion Starter · #19 ·
On 2007-01-16 22:49, Bonnie1000th wrote:
NOW, I'm wondering if the uneven header length will cause any issues.... >>>
Mase, for your unique application, will be better for you to jet your bike on a Dyno with gas analizer, one cylinder at the time, because dynos has a single gas analizer and you have not a crossover.I'm almost sure that each carb will have different jetting.
An air box elimination kit, will be a must, with such a frew flow exhaust system.
I hope this help.
Carlos! where have you been. We didn't meet up...
I got sick anyways. You gotta see the exhaust. it's coming out killer.
I'll call you tomorrow...
 

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Carlos! where have you been. We didn't meet up...
I got sick anyways. You gotta see the exhaust. it's coming out killer.
I'll call you tomorrow... >>>>

Sorry man, been very busy at work!
Saturday I will have to go to L.A, lets see if we can see each other, it will be great to see that BA exhaust!
Will talk tomorrow(hope you feel better)
Later! :razz:
 
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