G oog le BadWeB | Login/out | Topics | Search | Custodians | Register | Edit Profile

Buell Forum » Quick Board Archives » Archive through February 11, 2004 » CV40-worth modifying? « Previous Next »

Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

Captainkirk
Posted on Saturday, January 31, 2004 - 01:06 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I'm running a CV40 with Thunderslide kit now. After reading up in the KV and talking with several Buelligans I've been advised to chuck the CV40 in the gravel. Before I heave it for a Mikuni HSR 42 I've got a couple questions for those of you who might know;
1) Lots of you have installed T-slide kits. Has anyone gone further with it to see how much performance you can wring out of it?
2) Speaking of which...what mods work well in conjunction with the T-slide? Which ones DON'T?
3) When building street motors for cars, a mechanical secondary carb has more performance potential, but the vacuum secondary design is more forgiving of tuning errors as the motor only takes what it needs, not what you force-feed it. Same principle on CV vs slide carbs? If not, why not?
4) Aaron has stated in the KV that while the HSR gives a much more noticeable felt response, actual HP graphs didn't show a heck of a lot of difference. Could this be due to the "lag" caused by the time required for the diaphragm to raise the slide vs the "direct connection" of the slide carb? If so, can this be overcome by yet a lighter spring...or, say, a Thunderjet?
4) Last but not least...I haven't seen much posted about the Edelbrock KwikSilver carb. I know they were installed on some earlier CA bikes. How do they compare to the HSR? Your thoughts, please......
Top of pagePrevious messageNext messageBottom of page Link to this message

Buellerthanyou
Posted on Saturday, January 31, 2004 - 01:30 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Don't know if this is any help, but I found this web page awhile back: http://www.nightrider.com/biketech/hd_cv_mods.htm
It seems more directed towards H-Ds...
80+ horsepower? WOW!

HellBuelly J
http://groups.yahoo.com/group/hellbuellies/

"We shall wheelie on the beaches. We shall wheelie on the landing grounds.
We shall wheelie in the fields, and in the streets;
we shall wheelie in the hills. We shall never surrender!"
--Winston "Buelldog" Churchill
Top of pagePrevious messageNext messageBottom of page Link to this message

1320
Posted on Saturday, January 31, 2004 - 08:46 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

You might be surprised what you can do with the CV...As a suggestion you might e-mail Paul Batts at www.battsracing.com and ask him what he has done to his CV. He holds land speed records on a STOCK motor 98 S1 with the CV carb. He told me that at the time he didn't know any better so he tried some mods to the CV and they worked so well that he has seen NO reason to change carbs...
Top of pagePrevious messageNext messageBottom of page Link to this message

Buckinfubba
Posted on Saturday, January 31, 2004 - 09:05 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

If anything go with the 44mm cv carb. they work great and tuning is much easier.
and if its worth anything to ya.
on our x1 and S1 race bikes we use the cv's because they seemed to work better than the mikuni's
thats just our experience tho. and there are a million opinions on this.

Brian
Tilley hd/buell
buckinfubba@hotmail.com
Top of pagePrevious messageNext messageBottom of page Link to this message

Aaron
Posted on Saturday, January 31, 2004 - 09:57 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I've had too much trouble with the 44's. If a guy wants one in his project, I just tell him right up front I'll sell it to him but I won't take responsibility if it won't tune right. I just can't afford to eat 3 or 4 hours on the dyno trying to make a POS work and I don't need the hassle of trying to exchange it for another that might or might not work right. Been there, done that.

The Mikuni, by comparison, is a pleasure to tune. Jet changes take 60 seconds instead of 20 minutes. Easy to get a flat A/F because they don't vent the bowl into the intake stream. Throttle response and power are outstanding. It's a nice product.

I really don't have any trouble tuning CV40's, but they start becoming a constraint above 100hp, which ain't enough for most people. I'm not a fan of any of the kits, I've seen too many times when they did more harm than good. It takes less than $20 worth of parts from the dealer to make a CV40 work right.
Top of pagePrevious messageNext messageBottom of page Link to this message

Buckinfubba
Posted on Saturday, January 31, 2004 - 10:14 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

aaron
your right about changing the jets. a lot easier with the mikuni.
Top of pagePrevious messageNext messageBottom of page Link to this message

Dynarider
Posted on Saturday, January 31, 2004 - 10:35 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I had a modded CV40 & while it was decent, the Mikuni 42 rught out of the box is a better carb. Easier cold weather starts, better throttle response.

With the CV no matter how it was modded I would still get some stumble during cold weather. Im talking 50 & below, but with the mikuni that all cleared up with no other changes at all.

You couldnt pay me to go back to a CV.
Top of pagePrevious messageNext messageBottom of page Link to this message

Captainkirk
Posted on Monday, February 02, 2004 - 12:13 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I guess what you're all saying is...chuck it in the gravel?
Top of pagePrevious messageNext messageBottom of page Link to this message

Bads1
Posted on Monday, February 02, 2004 - 12:18 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I had the Mikuni on my tuber and the throttle response is amazing over the the CV40.
Top of pagePrevious messageNext messageBottom of page Link to this message

Opto
Posted on Monday, February 02, 2004 - 01:42 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Aaron stated it and I've read many times that CV40's are fine up to 100hp. So unless you're unhappy with the response of your CV or going for 100hp+ I really can't see the point of spending money on a Mikuni. I was really happy with the CV on my old 1200 Sporty, but then it wasn't flowing as much air as a Buell. Can you manage a test ride on a bike with a Mikuni to compare the carbs?
Top of pagePrevious messageNext messageBottom of page Link to this message

Loki
Posted on Monday, February 02, 2004 - 06:20 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Bubba,

email me I got a couple special questions for ya.

Loki
Top of pagePrevious messageNext messageBottom of page Link to this message

Captainkirk
Posted on Tuesday, February 03, 2004 - 12:40 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Opto-
Yeah, but unfortunately(?) it's got a few more goodies than the Mikuni....
Unfair example, methinks!
Top of pagePrevious messageNext messageBottom of page Link to this message

Bob_thompson
Posted on Thursday, February 05, 2004 - 11:31 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

As we know there is something said about fluctuation in air flow when using the lighter slide spring or cutting the stocker and drilling out the vacumn vent but is this something you can actually feel while riding or is this just something that shows up on a dyno run. How about some actual riding experiances. Thanks much, Bob
Top of pagePrevious messageNext messageBottom of page Link to this message

Bomber
Posted on Thursday, February 05, 2004 - 02:23 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Bob . . . .. well, I can feel a diffrerence in my modded CV40 . . . .did the spring and needle and jet changes, to attempt to "scientifically" test the effects with my butt-dyno . . . .the difference IS there, according to my butt (which has not been calibrated in quite some time . . .no ISOO-9000 for me, I'm afraid) . . .

N.B. -- Y2K M2, wileyco and v&h cans (depending) and aftermarket aircleaner . . . . way under 100hp, which is the limit for these carbs according to all sorts of gurus (one of the few things they all agree on {grin})
Top of pagePrevious messageNext messageBottom of page Link to this message

Bob_thompson
Posted on Friday, February 06, 2004 - 11:24 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Bomber, thanks for the input. Did you notice any surging in the crusing or midrange? Also, where did you feel the seat of the pants change? Bob
Top of pagePrevious messageNext messageBottom of page Link to this message

Bomber
Posted on Friday, February 06, 2004 - 12:26 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Bob -- surging yessir until I completed the mods (spring, then needle, then needle and shim, then jets . . . . .) . . . . if I had made the mods all at once, like a sane person, I would not have noticed the surging that went away when the mods were completed . . .. .

the dip in the mid-range seems to have vanished (although a dyno run may prove that it is only diminished, not banished altogether), and the throttle respnse seems a little snappier, as well . .. . if possible, the mods made the MaDeuece into even more of a locomotive than it was stock . . . . just pulls and pulls and pulls . . . . .
« Previous Next »

Add Your Message Here
Post:
Bold text Italics Underline Create a hyperlink Insert a clipart image

Username: Posting Information:
This is a private posting area. Only registered users and custodians may post messages here.
Password:
Options: Post as "Anonymous" (Valid reason required. Abusers will be exposed. If unsure, ask.)
Enable HTML code in message
Automatically activate URLs in message
Action:

Topics | Last Day | Tree View | Search | User List | Help/Instructions | Rules | Program Credits Administration