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XL883
25th May 2006, 20:27
Had the SE11 Slash Down mufflers installed yesterday at the dealer and like the sound a lot over the stockers. My observation is.....while I was riding the 55 mi. home it seemed as though I was experiencing a bit more vibration than before the SE11's were put on. Before leaving the dealer I was talking to the tech who did the work and he said he changed the slow jet to a 46(?) and turned the mixture screw (or at least I think it was the mixture screw; the one that has to have the plug drilled out) out 3 turns, and he adjusted the idle down a little.

Question is would I expect to feel a bit more vibration after having this done or is it maybe it wasn't tuned correctly?

-2003 XLH883 (Stock, except for the mufflers now)

Thanks

Tom

cphilip
25th May 2006, 20:30
I would not have expected him to have to do all that carb tweeking with just a set of SE II's installed....

OldFenderGuy
25th May 2006, 20:46
I would not have expected him to have to do all that carb tweeking with just a set of SE II's installed....

I agree with that 100%, especially if the bike was running fine before the muffler swap..

http://dogsdoom.com/PI/1200sig10.jpg

chrishajer
25th May 2006, 20:51
1. Did the repair order say anything about rejetting the carb and installing an air cleaner?

2. There is no 46 pilot jet for Keihin CV.

3. Generally vibration goes down when you install aftermarket mufflers, because the weight is less than the stockers. Less weight on the end of a long lever (your rear muffler bracket) translates into less vibes for you.

4. It is possible that the mufflers are in a bind, meaning when everything was installed it put some tension on something (a fastener, brackets, something like that) and the components under tension are increasing the vibration feedback. This happens more often with full exhaust systems than slip ons, but I suppose it could happen.

5. If the bike was NOT rejetted, my guess is that the jetting is just wrong for the mufflers, and the motor is not happy. Get it jetted for the mufflers.

--Chris

XL883
25th May 2006, 21:00
I was having those "carb farts" also, so I asked the dealer's service guy where I had the pipes installed to tune it up to get rid of them. When I bought it last September and test rode it I mentioned to the selling dealer about the 'miss' that I noticed sometimes when you wick on the throttle and he told me at that time it needed a jet kit installed because these are set lean from the factory for emissions and that the installation of a jet kit would cure that so I asked the dealer the other day when I had the pipes installed (different dealer) to tune it to get rid of that problem as well. Also the dealer where I bought the SE mufflers (not the same who put the pipes on etc.) said that it should be rejetted because with the install of these mufflers it would probably run hotter if I didn't re-jet.

Should I have the carb put back to normal or is there something not quite right with what they did. Appreciate the help.

Tom

chrishajer
25th May 2006, 21:04
True they are lean from the Factory.

True you should rejet when you install new mufflers.

You should not put the carb back to normal. I think it might just need some more tuning. But if it runs well, and it's been rejetted, then the vibration is from something else.

--Chris

edman
25th May 2006, 21:14
2. There is no 46 pilot jet for Keihin CV.

--Chris

J & P 46 pilot jetl (http://www.jpcycles.com/productdetail.aspx?PID=400-861&cs=Harley&GID=5BBC6782-3442-4EF9-9EFC-59E69BC74AE0&store=&page=&search=)

Just being an ass :) I don't think HD has one.

cphilip
25th May 2006, 21:20
They should only have rejetted if it NEEDED to be rejeted. And then only to the point it needed. Wether that be just a pilot or both the main and pilot.


But I found my install of a set of SEII's did not want a rejet. In fact I found it was a tad RICH from the factory. It actualy warmed up better and no carb farts at all anymore with the simple SEII install. I had a kit on hand. Just let the bike talk to me a bit before I decided. and it liked it where it was. However I did rejet when I put a K&N in and modified the air box. But I only had to put a 45 pilot in to make that happy. Nothing else. Had I done something more drastic that might not have been enough. But it was. The bike will tell you. Nothing else will.

Are we forgetting about the dampening effect of more weight out the ends dampening the vibrations? Because its not an unknown phenomenon and it actualy can be quite the opposite. Less weight out there can indeed create more vibration. It may not be jetting.

chrishajer
25th May 2006, 21:23
Are we forgetting about the dampening effect of more weight out the ends dampening the vibrations? Because its not an unknown phenomenon and it actualy can be quite the opposite. Less weight out there can indeed create more vibration.
Interesting theory.

I suppose that's the theory with bar end weights...

--Chris

cphilip
25th May 2006, 21:36
Interesting theory.

I suppose that's the theory with bar end weights...

--Chris

It is... indeed. And some say it works some don't.

chrishajer
25th May 2006, 21:49
That's why it's theory :)

Like global warming....

--Chris

cphilip
25th May 2006, 21:50
Mmmmmmmzactly! :D

johnkiddier
26th May 2006, 17:31
I installed cycle shack slip-ons (similar to SEII) and rejetted to 1 45 pilot. I didn't notice an increase in vibration until I borrowed a bone stock xl883r from the dealer whilst mione was in for service.

Seemed like a sewing machine in comparison. Mine has more vibration along with more noise. The increased vibration doesn't cause me any doscomfort though. If you've got a rubber mount it's worth checking the engine mounting bolts aren't loose though.

JK

XL883
27th May 2006, 00:31
To All:

Apologise for not responding promptly to the suggestions you have offered....I drive a truck and am not always at my 'puter' on a regular basis. I called the dealer back and spoke to the service mgr. who spoke to the tech who did the muffler install/re-jet/tweak and he said the tech replaced the stock slow jet with a 46, drilled out the plug and turned the screw out just a little bit. He suggested I ride it for a few days to see how it felt and if I wasn't satisfied to call him back and return to have it checked out further.

The increased vibrations I felt after the change are not really bothersome to me but I am just wondering if it needs a bit more tweaking to get it back close to what it was before (vibration wise) or if it is a result of the more free flowing mufflers that would be causing this. One thing I did notice was that the 'carb farts' have almost disappeared from what they were originally.

Again everyone, I really appreciate the comments and advise and I know it will work out for me with the help of you who have experienced issues similar to this. Thanks.

Tom

XL883
29th May 2006, 19:14
Had a little spare time on my hands today so I pulled the plugs for a look and the electrodes were black, not overly sooty but just black (as compared to the whitish colour B4 the SE11 mufffler change and re-jet) and there was some black on the small white insulator part as well.
Seems like it may be running a bit too rich now and am thinking maybe this may also contribute to the increased vibration? Wondering if I should have the dealer change the jet to a 45 instead of the 46 he put in and see if this helps to make the plugs more of a tan colour.

Tom

Note: The air filter is still stock...

Clipper
29th May 2006, 23:32
I installed a set of S&S slash downs a while back and I'm also noticing a little more vibration at certain rpm's - right around 3K is the worst. Good below and good above that point so I figure it is some kind of harmonic that is causing it so I'm not too worried. Oh yeah, I did check the front motor mount and it needed to be tightened. Seemed to help some.

prplhays
30th May 2006, 20:51
Seems like it may be running a bit too rich now and am thinking maybe this may also contribute to the increased vibration? Wondering if I should have the dealer change the jet to a 45 instead of the 46 he put in and see if this helps to make the plugs more of a tan colour

I agree with NO 46 jet available statement, so they probably put a 45 idle jet in. I think the mixture screw is out way too far. Three full turns is just too much and that is why your plugs are black. Stock on the mixture screw should be 1.5 turns out. I have an 883 with CS slip-ons and an intake mod. It has double the mods so is doubly more likely to run lean without any carb mods. I have a 45 idle jet and my mixture is 2.25 turns out. It runs great, no carb farts and pugs are tan.

XL883
31st May 2006, 20:13
prplhays:

Is it a do-it-yourself job to get at the mixture screw and check the setting and would the carb have to come off to do this?

Tom

chrishajer
31st May 2006, 23:22
J & P 46 pilot jetl (http://www.jpcycles.com/productdetail.aspx?PID=400-861&cs=Harley&GID=5BBC6782-3442-4EF9-9EFC-59E69BC74AE0&store=&page=&search=)

Just being an ass :) I don't think HD has one.
Ha!

You learn something new every day. I will S.T.F.U. now.

--Chris