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Are the Mukuni's worth the $900 more dollars than the CR's?
My 790 engine is stock except I have Staintune exhaust and am about to order a air box replacement and K&N filters.
jamboa
 

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I guess it the same cleche. "You pay for what you get".Are you going with the carbs before you do the big bore?
Jamboa
 

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hopefully all at the same time, so I can have my head port matched to the intake manifolds that come with the carbs, bore that baby out to 41mm.

I'm trying to sell off a project and a ton of parts which will cover the big bore, +2mm intake/+1mm exhaust valves, port and polish head, install sleeves in cylinder for big bore, and the carbs...

total of almost 3k, not including shipping or my labor, and other gaskets/odds and ends I'll need.

I'm hoping for 85rwhp and 65-70 ft lbs (all at the wheel).
 

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I have heard nothing but mixed reviews of the CRs, and SCCTrim has a 80+ rwhp dyno run to prove the mikunis work (along with a big-bore). I'm going to order a pair in the next couple of weeks.
Machine, of course 40cc's wil make a difference but is it worth the cost? My feeling is that the 904 kit makes sense for 790 motor but not the 865? I go with the rest of your recipe and I'm assuming you'll go to 10,5 compression? Well that's what I'm thinking. I'd keep the same cam duration maybe a little more aggressive flank, some cam advance, and with the bigger valves and flat side carbs your VE should shoot up. But then I'm not an engineer. I will watch you project with interest. Any thoughts an programmable ignition modules?
 

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additional cc's isn't where the power come's from. While there's some truth to the old adage that there's no replacement for displacement, the truth with the 904 kit is the power come's from the additional compression. Even if you have a 865 motor the 904 kit is worth it.


Regarding mikuni's/cr's....buy the mikuni's, they come with a air box elimination kit as well as billet intake manifolds. The reason I suggest them is 1: you buying a 42mm carb, the cr's are the same size carb but built differently...basically the cr's don't have any restriction's in the throat while at wot, that and they are not a constant velocity carb.

The mikuni's are flat slides, they are very basic in design, and rather easy to totally disassemble/reassemble. Difference in drive ability is negligible, unless you wack the hrottle from 1/8th to wide open at a rpm under 2500 or so. The reason for this is that they are not constant velocity carbs.

After installing the mikuni's you'll find that you dont need to twist the throttle nearly as hard to get the same end result, install a 904 kit and you'll twist it even less to get the same result.

My bike make's 82+ hp and 61lbft of torque..( with the accel pump's enabled...they should not be )...with stock headers, predators, billet intakes, mikuni 42mm hsr's, 904 kit, exhaust cam advanced 1 tooth, and a upgraded ecu. I also have a 18 tooth front sprocket, which doesnt affect the hp, just take's the bike longer to come on.
 

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I just bought the Mikuni's for my bike - I talked to a friend who started with the Cr carbs, then switched to the FCR 39's and has run those on Guzzi's Duc's and Bonnevilles, and he felt the HSR's are the way to go. I also spoke with Bill at Bonneville performance and came away pretty confident with all the mods to my motor that the Mikuni's are for me. I was worried about the carbs being too big but after speaking with Bill and reading SCC's threads, I can hardly wait. JCW :hammer:
 

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On 2006-11-30 09:28, sweatmachine wrote:
bonneville performance carb kits
Are you freaking kidding me!?!? I usually don't get sticker shock, but HOLY CHA-CHING BATMAN!!! $1500 seems rather expensive to me for what " I " consider to be a minimal amount of HP gains here. Maybe I haven't researched this subject well enough ... :???:
 

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the kit includes more than just the carbs, but I'm sure there's a "fair" amount of markup at play.

There are a few machined parts in Bill's kit that make the carbs easy to install, easy to sync/balance, and easy to ride, choke/idle control/etc, and his kit includes a new throttle assembly, airbox removal, billet intake manifolds, etc.

There's a lot of parts beyond the carbs, plus from what I hear they bolt right on and Bill really helps with tuning them up right.

I'm sold!
 

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Jamboa2003 I was on the preformance bonneville page and the have the carbs listed for 555 without buying the kit.Another company to talk to is www.sudco.com they have the cr and fcr kehin carbs,never looked for the mik's,but I'd have a look befor you spend 1300.
 

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On 2006-11-30 13:27, POPPE wrote:
Jamboa2003 I was on the preformance bonneville page and the have the carbs listed for 555 without buying the kit.
Sudco lists the carbs for $399. Still not sure I would pay all that extra money for his "kits" - that seems excessive to me. Just sayin.

[ This message was edited by: Bonafide on 2006-11-30 14:01 ]
 

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1450 for the kit from bill, this also gets you bill's tech support. Bill is a highly skilled engineer, he knows his stuff.

Along with the carbs, you also get a air box elimination kit. Also included are billet intake manifolds, which I believe are polished.

Also, the carbs are a bolt up deal, they are mounted to a custom machined bracket, already synchronized, you get the cables, the joker machine throttle assembly, all the necessary hardware. New pod filters, everything.


Now take the sudco cost, double it for 2 carbs, add the cost of the air box elimination kit, the billet intakes, fab your own bracket to bolt the carbs to, and your own carb brace, sync the carbs up, make your own cables, and support yourself with your own technical experience.

Don't forget the joker machine throttle assembly and having the carb's properly jetted in advance. Also add the choke assembly.


Bottom line...it's worth the price.
 

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hey Trim, since you're the only one that actually has them on this forum...

how's the new throttle? you said it takes less movement to gain more opening? is it like a 1/4 turn race throttle kinda thing?

The stock throttle takes a lot of movement to whack all the way open, I'd love for the mikunis to have nice short throttle throw to WOT.
 

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Comparatively speaking I think the throttle throw is maybe a little less to wot, but what I actually meant was since the motor is making so much more power you dont have to twist it nearly as hard to achieve the same end result when compared to stock.

A smooth twist of the wrist from a throttle position of say 1/8th to 1/2 produce's arm straightening results. The bike is awesome to ride. I finally had the chance the other day to ride with my neighbor, he has a new hd streetbob. Nice bike, he used to pull me pretty hard when my ride was stock.


...the bike now come's up way faster than his, and he isnt gaining ground till 100+ mph.


<insert huge seg here>
 

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ahh, a verified Harley spanking.

Really that Street Bob is a cool bike. Kinda like HD's version of a Bonnie Black.

I can't wait to get my motor built up. Probably be a couple months until it's all said and done. I have a buyer for the XS650, but I have to go through some BS with the title that's going to hold things up for a couple weeks.
 
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