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Discussion Starter · #1 · (Edited)
CR Carbs..........Jury is IN!!

Had the CR carbs installed today.....supposedly jetted properly from Sean @ BC.

First, I don't notice any appreciable gain up to 60MPH. Second, I think that it's a tad rich on the mixture as I have a strong odor of gas during idle and after shut-off. I'll have to deal with that.

Not sure as to how to approach those issues.

Third, the throttle is very stiff compared to the OEM carbs due to direct link Vs. vacuum. (this anomaly is very much influenced by not being used to a racing type carb set-up.)

Overall, I think that it is too rich and will seek guidance on how to remedy it.

I don't know if I'm gonna like this after all. Time will tell, I guess.
 

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Anbody can take a guess at jetting your carbs - but no one can do it properly without touching your bike.

I think most folks err on the side of caution when shipping "prejetted" carbs.

The prejetted FCRs I received ran:

12:1 @ idle
13:1 @ 1/4-3/8
16.5:1 @ 1/2
10:1 @ 5/8 - 7/8
Rich enough to puke at WOT

Pretty disgusting!
 

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run it wot for a few sec in high gear then back off to 7/8 throttle if it dont pick up power on let off go down on main jets and do it again .keep doing that till you find what jet makes it pick up on let off then go back up 1 size you will be close.It is better to do that on a good high air pressure day .that way you will be safe every day .If you do it on a bad air day you might be lean on a good day. Hope that makes since.
 

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Discussion Starter · #4 · (Edited)
run it wot for a few sec in high gear then back off to 7/8 throttle if it dont pick up power on let off go down on main jets and do it again .keep doing that till you find what jet makes it pick up on let off then go back up 1 size you will be close.It is better to do that on a good high air pressure day .that way you will be safe every day .If you do it on a bad air day you might be lean on a good day. Hope that makes since.
Well, I feel stupid posting BEFORE I really had a chance to fully test the install. Which I did today.

No regrets whatever. This thing is an ANIMAL when you can rack the throttle.

Did what you suggested Mike and she just KEEPS ON PULLING.

Chickened out at 90MPH. That, by the way is the speed record for me on this baby.

Also this is strange...no smell of gas anymore. I think Sean jetted it right. But maybe she needs and adjust on the A/F screws, just a tad. Performance is EXCELLENT!

When I rode home yestidy after the marathon install at the dealer, (I was there for six hours)THEY ONLY CHARGED ME FOR TWO HOURS LABOR - I was a bit subdued (to say the least) and rode all the way on a stoplighted boulevard where I could only gradually get up to about 60MPH. (Speed limit was 40MPH)

Today, I really put her through her paces and as I report, WILL NEVER GO BACK!

They look pretty bitchin' too.:D Got rid of a whole bunch of hose mess in the bargain when the OEM's were ditched, and she looks waaay cleaner.

I'm a very happy camper. My Bonnie looks stock with bling...but she sure isn't!:D

For the record; I would never go back on any of the performance mods that I have made to this bike. Maybe, I have been lucky, I dunno. But I am done as far as this one's concerned.

When I have room inside for another bike, I'm thinkin' a STREET TRIPLE-HA!
 

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That's good news, glad all is well. It is always important to do the WOT test.

Lots of times! :D
 

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Discussion Starter · #6 ·
That's good news, glad all is well. It is always important to do the WOT test.

Lots of times! :D
Yes, WOT is the thrill. However, where I live, the cops hide in the oaks, with brush stuffed into their bikes and put deer antlers on their helmets while they run their radar.:D

One has to be very careful and discriminating as to where it's safe to run WOT.:D
 

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No regrets whatever. This thing is an ANIMAL when you can rack the throttle.

Did what you suggested Mike and she just KEEPS ON PULLING.

Chickened out at 90MPH. That, by the way is the speed record for me on this baby.
I got my CRs fitted last Wednesday and gave them a good thrashing running out to the lake and back this weekend. Seat of the pants dyno says nothing lost down low, some gain through the midrange to top end. For the first time, the bike pulls top gear strong...I too chickened out before leveling out, but I saw 120 indicated before bringing her back down. The bike was still pulling at that point. Wheee.

Dyno run to follow.

Cheers,

--Rich
 

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If you can't tune carbs take them to a shop so they can tune and jet them right . There is a considerable difference between the CVKs to CRs . You'll never be able to crack them like a CVK but a roll on and with tuned carbs the bike will just take off. I love mine .
 

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A rapid shutting off of the throttle also produces a hiccup. The price for the FCR's seemed steep when undertaking the pre-buy justification but now I have them...sensational. They add so much fun in corners and roll-ons on the highway. Hopefully the new 813 cams translate to the same 'fun factor' :D And new cams means no change to my carb settings
 

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Third, the throttle is very stiff compared to the OEM carbs due to direct link Vs. vacuum. (this anomaly is very much influenced by not being used to a racing type carb set-up.)
if you haven't already, try lubing the cables, and I mean LUBE them. I sprayed 1/4 of a can of chain oil and a few ounces of engine oil down my throttle cables and into the throttle mechanism itself. The HSR Mikunis have a notoriously stiff throttle action and mine are now smooth as hot BUTTAH!
 

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if you haven't already, try lubing the cables, and I mean LUBE them. I sprayed 1/4 of a can of chain oil and a few ounces of engine oil down my throttle cables and into the throttle mechanism itself. The HSR Mikunis have a notoriously stiff throttle action and mine are now smooth as hot BUTTAH!
lol sissy hands
 

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Discussion Starter · #16 · (Edited)
change order....

:( Well today I started her up cold. Thought I'd check out the choke.

Starts right up without the choke but, if you move that puppy a half a millimeter, it kills the engine, I mean right now!:( ***?

Also, I have been getting a burp or backfire from the right cylinder about 50% of the time when starting after warmed up. *** is with that?

When I took her through the paces yesterday, she ran beautifully, no flat spots in rev ranges and top gear at 90 MPH. Let off slightly at that speed and gas back on throttle,-keeps pulling.

Talked to Sean at BC who referred me to their tech. guy, Miles, who could not give me an answer on the choke issue but, said that I should look at the plugs for signs of too rich. Or, maybe it could be the needle position which is? I don't remember at this point.:confused:

What the hell size is the socket for the plugs? Nothing that I have is the right one.

Something ain't right here and, I need to sort it out.

Help is requested.
 

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I get a backfire sometimes from my 04 Bonnie 904BB w/CR35's. It can scare the crap out of you. I have put about 2,000 miles so far with out any trouble. I wish my Scrambler ran this good. Come September the engine mods will start.
 

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Discussion Starter · #18 ·
Also, at the end of the right sleeper pipe, there is soot. On the left silencer, it's clean/bronze.

Any help is appreciated guys.

Thanks.
 

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the spark plug takes an 18mm spark plug socket, available at sears or any auto parts store.

I wouldn't put much stock in reading the plugs though, or in any "expert" that tells you to read the plugs...really. I'd venture to say the butt dyno is more accurate than reading the plugs.
 

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Discussion Starter · #20 ·
Sweat, thanks for the reply. However, what do you think about the backfire issue on start & the fact that the choke just kills the engine at stone cold start-up?

That can't be normal with these carbs, or is it? I'm lookin' for an answer to this.
 
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