hiya, just got a 1992 FXDC with 50,000mi on it (after waiiting 15 years to replace my last 94 FXDL!). Don't know the history other than a lot of receipts for small works. She has an S&S Super E Carb and NGK Iridium BPR5EIX plugs.

I know she's running lean but can someone tell me if I risk damaging the engine if i keep running her. I want to get her sorted but not even sure if i should ride her to the garage!

Also there is a lot of blackening in the air intake, not sure if I can clean this or need to replace?

Also should i get a carb rebuild kit and have her tuned or just a tune up?

Bit of a newbie and dont want to create an expensive problem after waiting so long.
Thank for any input guys.

 

Running lean causes your engine to run hot increasing the risk of detonation. You most likely have one of two issues or both going on, either your jets are too small (less likely given the aftermarket carb) or your air/fuel mixture screw is set incorrectly. I would check your idle mixture screw first to get that sorted out. I am not the most familiar with S&S CV carbs so I cannot tell you exactly where the screw is but you can find a lot of content on S&S carb tuning on the internet.

 

Thanks Zanthamos, I'll check the settings. I've also found some instructional videos on the S&S website but will need to wait till i finish work!
I forgot to add the S&S Teardrop cover has been drilled with holes (aaahh!) and then patched pretty badly so not the best air intake set up - I am looking to change this but wanted to check that my pistons weren't going to melt before I sorted that.

 

You can fry your engine running to lean --- it's better to run rich than lean . Every thing you or that has been done to exhaust and air filter WILL make your engine run lean even a simple K&N filter change you have to slow jet your carb up appox 4 steps

 

Look for "pepper" specks on the porcelain. Or little tiny metal spheres/specks on the porcelain. Use a magnifying glass and a flashlight to look closely.

The metal spheres is your piston melting. The pepper specks are an indication that your getting real close to lean.

Your plugs don't look that bad from what I can see. Spend a little time reading this:

http://honda-tech.com/forums/forced-...ug***-3063102/

And this:

http://members.uia.net/pkelley2/sparkplugreading.html

YD

 

Thanks 81rat and Yankee Dog, excellent plug information, will be learning all that, didnt realise how much information you can get from the plugs! I did review the idle and air/fuel mix and replaced the air cover with a new teardrop (previous one has holes in it) and she is running a lot better . I think i panicked a bit. Appreciate the input.

 

If a carbed machine is running lean, it'll "pop" and "sneeze" continually.
Also on an S&S-equipped bike, the air-idle screw will be waaaaaay out past the approx 1 1/2 turns in order to attempt to get a decent idle quality.
Scott

 

Hi hillsidecycle, sorry, moved the problem over to "misfiring dyna" and still working on a solution which seems to be the PO put the piston rings on wrong and messed up the cylinders big time so now I need to see which is cheaper, to hone the cylinders or buy new ones.
I did however adjust the various screws on the S&S after watching the S&S videos which i thought were very useful and yup the idle is way passed. Thanks

 

If it was not popping or sneezing thru the carb from the suspected lean condition, I believe that the timing would be the issue creating spark plug concerns.
The 2 are confused by many.
Scott

 

Thanks Scott, the timing sensor was in fact melted so i had to change that. however that didn't fix it and it turned out to be the piston rings on the rear cylinder were so worn there was no pressure.

What is curious is that the garage that is fixing this told me that the S&S E carb I have on her is too "good" for my old bike (it's more for fast 'n' furious rides) and that the carb will probably be dumping a lot of fuel so making her run too rich - the fact that I had Iridium plugs on her was better for this but they recommend replacing the S&S with the stock carb. In the end I'm letting them sort everything out and they will "tune" the carb to best suit the old '92 Evo.
Cheers.