I am hoping yall can help me figure out an issue I am having with my 2001 Harley Sportster 883. Real quick, it does have the 1200 big bore aftermarket done. Additionally, and this was a while ago (since May 2015). I was having vacuum issues and replaced the vacuum pet **** with a gravity one. The one vacuum hose that still has to run to the carb is in place. I went from dragpipes (west coast choppers hellbent) to Thunderheaders. Modified the back of the air filter (the plastic) so it would get more air, changed the jets (per Dynoguy who said go up to a 48) and replaced the 883 needle with a 1200 one. I also installed a CV Performance Harley choke bracket and Harley choke cable. Ran great after all of this.
Now the issue, I was riding back from the Harley dealership (about a month ago) and the bike started running rough. As soon as I got home it died out and backfired real hard (not normal). Wouldn't start again. I took the air filter off and got a look at the carb. The accelerator pump rod was out the body. I am assuming that this was the result of the backfire as I did ride it home. I put it back in the carb and put everything back together. No change. Took it back apart and started going over everything. I found some tiny holes in the vacuum slide diaphragm and some oxidization on the accelerator pump diaphragm. I decided a rebuild was in order since it is a 14 year old bike and since I have had it (2003 purchase) the carb has never been done (minus jets).
Got it all back together, excited to be back on my scoot AND...nothing...runs like ****. VERY rough. Only starts to sound good when its about to run out of gas (leaner?). Black smoke from the pipes and gas misting from the throat of the carb (yes the accelerator pump nozzle is lined up right).
As I went to take it back off I noticed that the black plastic carb cover was cracked at one of the posts. I am thinking that a vacuum issue may be contributing to the issues so I have a
1x Harley Idle Speed Screw (I know, nothing to do with the vacuum) 1x Chrome CV Carburetor Cover
I am hoping this does it but I am not holding my breath. I did pull the plugs, black as midnight. My assumption is that it is too rich. That part that makes that hard for me to say is THE issue is that I have been running those bigger jets since June 2015 without ANY of these issues, so...
My plan at this point is to replace the cover and if that doesn't work put in smaller jets and just try walking them back on until it starts running smooth.
If you have a 48 pilot jet, that is too rich. Try a 45. Set the idle mixture screw 2.5 turns out from lightly seated as a start. Make sure you did not lose the needle jet (or put it in upside down), and that you have it installed correctly. Main jet of 180 should about right for 1200. Did you get a CVP needle, not needle jet as you posted? Did you get the old idle mixture needle packing out? Is your enrichener working properly, not staying on? Did you check for vacuum leaks at the cylinder heads/manifold joint? How about the carb seal to manifold? If it was fine with 48 jets, seems like something was not right for a while.
My CA carb has an additional vacuum port, it must be plugged off if you have one. It purges the charcoal can vapors into the intake.
No one runs a 48 pilot that I've read about. But, I could be wrong.
John
Last edited by John Harper; 01-20-2016 at 04:53 PM.
Needle jet is in place and facing the right way. Pilot jet wouldn't seat right otherwise (as I put it in upside down the first time). I do have a CVP needle in there for a 1200 instead of the stock for the 883 that was in there before. I didn't list it on the purchased parts as I bought that as well as the jets from a local shop. The old idle mixture needle packing is out and on the stock needle.
Enricher works. I have not checked the cylinder head/manifold joint as the guidance on CV-performance is to hold propane torch (unlit) in the area and see if the engine starts running sluggish. I, however, do not feel like being blown up. I bought the new little boot for the back of the carb at the manifold. My next step there is to get some grease to make sure its a good seal but that was never an issue before. It was idling much faster then ever before regardless of adjustment. Where is the other vacuum port you mentioned located?
After further inspection it is a 46 not a 48. The other is a 180. However, when I pulled the jet it looked like this.
Last edited by Doc Smoke BMCR; 01-20-2016 at 07:39 PM.
Reason: New information
45/180 or 185 jets, 2.5-3 turns on the mixture screw. Need a new idle jet as that one is buggered beyond use.
Make sure the diaphragm isn't pinched and is working properly.
Checking for leaks is ok with an unlit propane torch. It won't blow you up. I've done it before. If you have an intake leak it will be very obvious using the torch. It should only take you a matter of seconds to sweep the manifold and find out.
Last edited by Scuba10jdl; 01-21-2016 at 08:17 AM.
45/180 or 185 jets, 2.5-3 turns on the mixture screw. Need a new idle jet as that one is buggered beyond use.
Make sure the diaphragm isn't pinched and is working properly.
Checking for leaks is ok with an unlit propane torch. It won't blow you up. I've done it before. If you have an intake leak it will be very obvious using the torch. It should only take you a matter of seconds to sweep the manifold and find out.
Alright. I'm gonna pick up (hopefully) new jets today. Went over the diaphragm and double checked everything last night. Once I get the bike even idle I'll check for leaks but you see ploom of boom in San Diego it's me f*cking up the propane test hahaha
Alright. I'm gonna pick up (hopefully) new jets today. Went over the diaphragm and double checked everything last night. Once I get the bike even idle I'll check for leaks but you see ploom of boom in San Diego it's me f*cking up the propane test hahaha
I'm up in Carlsbad, don't get to jiggy. We already got burned out two years ago.
The CA vacuum port is lower down from the top vacuum port, on the fuel inlet side. You'd see it.
"Needle jet is in place and facing the right way. Pilot jet wouldn't seat right otherwise (as I put it in upside down the first time)."
Did you screw the pilot jet into the mainjet holder/emulsion tube? How did it get bent like that? Oops? It happens.
John
Last edited by John Harper; 01-21-2016 at 06:44 PM.
Poor wording. i did not in fact put the pilot jet in there lol. Main jet. No problem there. I am not sure how the pilot jet got all effed up but my guess is that I just cinched it down WAY too much.
01-20-2016, 04:02 PM
2001 Sportster 883 Carb issue
