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Truedog
Posted on Thursday, September 20, 2012 - 10:55 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

OK, I am getting sick and tired of fighting my fuel injection problem on my 2001 S3T. I am thinking that I will convert to carb this winter. Any special considerations? I believe that all I need is:

Carb intake manifold

CV 40 or Mikuni carb

Replace fuel pump with petcock and close up extra opening in tank

Continue to use stock ignition and remove CEL bulb.

Will stock FI cables work with carb? If not where to I get the correct cables?

Will the cables for earlier carbureted S3T work?

I saw posts about a "gutted fuel pump" - Huh?
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Wack01
Posted on Thursday, September 20, 2012 - 03:42 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Yes my bike is running all stock except the tank
http://www.youtube.com/watch?v=WZRvsjbiW9w&feature =plcp
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Wack01
Posted on Thursday, September 20, 2012 - 03:47 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Also I will buy that pump off you if it works.

More info
http://mcmod.com/EFIconvert.html
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Jayvee
Posted on Thursday, September 20, 2012 - 04:14 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

"stock ignition"

Isn't the F.I. ECM for X1 different from the carb'd M2?
The ignition trigger rotor sure looks different too.
Were early S3's carbureted? If so, I'd get the parts from one of those.
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Someday
Posted on Thursday, September 20, 2012 - 04:49 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

'97 & '98 S3's were carburated. Went to FI in '99.
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Truedog
Posted on Friday, September 21, 2012 - 02:47 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Hopefully I can make this work with minimal outlay of cash and improve the rideability.

As much as I have enjoyed this bike for the last 11 years, these FI issues are driving me nuts, especially as no one local can help me out.

If money was no issue I'd go trade this bike on a new HD Switchback tomorrow. Sadly money IS an issue.....
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No_rice
Posted on Friday, September 21, 2012 - 05:17 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

If money was no issue I'd go trade this bike on a new HD Switchback tomorrow. Sadly money IS an issue.....

you mean LUCKILY! ; )
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Ratbuell
Posted on Saturday, September 22, 2012 - 09:27 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Why not start with "what sort of EFI problems are you having?".

Chances are, someone on this board has run into (and solved) the same problems...
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Truedog
Posted on Saturday, September 22, 2012 - 04:40 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Here's what I've been through.

http://www.badweatherbikers.com/buell/messages/476 23/679361.html?1342573319

Tried two different throttle bodies and 3 ECM's (2 race).

New IAT, head temp sensor, O2 sensor, and fuel pump. only a code once in a while for engine temp..

I do NOT have ECM SPy or cable.
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Harleyelf
Posted on Saturday, September 22, 2012 - 05:50 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I use a module from a '98 M2, which is a Sportster part. I matched it to a Drag Specialties cam position sensor (don't forget to change the trigger rotor, too) and a dual-fire coil and plug wires from the same M2. I'm running an antique SU car carburetor from a fifties jaguar so I use an intake manifold with old-style bolt holes like an ironhead sporty uses. Been three years and I've never looked back. Idles like a rock and accelerates like a rocket. I changed the tachometer to a '98 S3 part to get rid of the engine and low fuel lights. My gas tank has both fuel pump holes plugged with nuts, bolts, and nylon washers - I drilled a petcock hole at the low point back by the battery and use an M2's petcock.

You'll need a VOES for the carbureted module as there is no provision for a TPS on the carburetor.

(Message edited by harleyelf on September 22, 2012)
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Coxster
Posted on Saturday, September 22, 2012 - 11:09 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Harleyelf = genius : )
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Blks1l
Posted on Sunday, September 23, 2012 - 04:07 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I used the stock FI cables on my carb, I did have to use a stand off/extension for one of the cables at the carb, I was able to pick that up from a local aftermarket HD shop. I did use the stock/race ignition, I don't use the VOES, and have no issues.
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Harleyelf
Posted on Sunday, September 23, 2012 - 10:23 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Don't forget to brace the carburetor to the head so your intake seals aren't supporting the carb's weight.

Your root issue may be the cam position sensor. Change it out before deep-sixing the whole DDFI.

(Message edited by harleyelf on September 23, 2012)
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Ratbuell
Posted on Sunday, September 23, 2012 - 11:12 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

..and I'd suggest getting ECMspy before ditching EFI.

If you can't diagnose...you're throwing darts in the dark.

(unless you just *want* to ditch it all...)
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Harleyelf
Posted on Monday, September 24, 2012 - 11:48 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The scoreboard for throwing darts in the dark includes columns for wall, floor, and foot. Others have gone before you on this quest - benefit from their experience.

If your coil is good and your module is good and your injectors are good and your wiring is not at fault, failure to run smoothly is much more likely to be caused by the sparking sequence than the fuel delivery system. Diagnose it like any other electronic ignition. Module, sensor, coil, plug wires, plugs. In cars the distributor sensor fails; on early DDFI Buells, it's the CPS. Same function.
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Truedog
Posted on Tuesday, September 25, 2012 - 10:38 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

How do you check the CPS? Where would I buy one if it's bad?

The bike runs good when cool and at WOT, but at part throttle or idling once hot it's terrible. It seems to be running worse since replacing the fuel pump with one for a Mustang. I may pop the original pump back in on the weekend if I have time.

Yesterday when I got home I got a CEL after it sat idling for 10-15 seconds. Code 14. I pulled the plugs and they indicate a lean condition. What next, without throwing buckets of money at the bike?
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Numb_nutz
Posted on Tuesday, September 25, 2012 - 07:19 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I switched mine a couple of years ago. You can just put the carb and intake on it will run with the ecm you have, I switched my tank to a m2. I was having trouble getting enough fuel before. Also not that easy to fit a fuel valve into a tank that wasn't made for it. I did switch to after market single fire ignition but didn't notice much difference. For what its worth, i had the same problems with my s3. it was the best thing i could have done. Love the bike now.

(Message edited by Numb Nutz on September 25, 2012)
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Harleyelf
Posted on Tuesday, September 25, 2012 - 07:31 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

An oscilloscope is the only sure way to check for unwanted sparking. The cps units often smell fried when they fail. Just swap a new one in; it'll work with the carburetor if you still want to go that route and don't want to change ignition modules.
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Kc_zombie
Posted on Wednesday, September 26, 2012 - 11:22 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Wow, an SU carb on a Buell! That is just plain awesome. I couldn't get the damn things to work on my 74 midget. Genius, just genius!
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Harleyelf
Posted on Thursday, September 27, 2012 - 12:44 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

It was already attached to a ironhead Sportster adapter when I bought it. Had it rebuilt by a guy in Colorado and bought a Revtech intake manifold which matches up quite nicely with the bolt holes of the carb's adapter flange. I love being able to adjust the mixture at will. We get air pressure variations here in Florida.

Sportster ignition parts are quite dependable. Coil, module, cam position sensor, and VOES are all available if you just don't say the word "Buell" to the parts counter guy.
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Truedog
Posted on Tuesday, October 02, 2012 - 11:19 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

For the moment my bike seems to be running better. I reinstalled the old fuel pump and the lean condition went away. While I was at it, I pulled the head temp sensor, cleaned the area and reinstalled. Also checked grounds and use reseated the ECM connectors. So far so good, but won't know for sure until the weather warms up again.

I'm still contemplating getting a new bike at some point. I've really enjoyed the S3T for the last 11 years, but am getting ready to move on when I can afford it. As I get older and less limber I find myself drawn to a little more comfortable and laid back bike. I test rode a new H-D Switchback on Sunday and I REALLY liked it. There was one issue, but not a problem with the bike. Someone at the dealership had removed the right side saddlebag, but did not latch it in place when the reinstalled it. Consequently, a couple miles into my test ride, while I was accelerating away from a stop sign and hit some rough pavement, the whole bag fell off and tumbled across the road, getting badly scratched and scuffed. I wasn't liable since one of the salesmen had left it loose, but I still felt a little weird rolling back into the dealership on a brand new bike with a damaged saddlebag.
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