Ironhead Mid-range strangeness...

[(WI)IceDevil]

I'm new to Harley's (and bikes in general), so bear with me and my very limited knowledge.

I'm getting some strange noises when cruising in the mid-range. It's not a pop or a backfire, more like the sound of someone shaking a few stones in a metal watering can. It seems like the sound is coming out the pipes, as opposed to from the motor. Only happens in 3rd gear @ ~30 mph and more noticeable in 4th @ ~40-50 mph. Any ideas?

I know she needs a good carb cleaning (possibly new jets) and could probably use plugs and wires (points & condenser too?). I'd really like to make this last.. absolutely love the bike. Like I said, I'm new to this.. so, please, be gentle.

-Jim

[(WI)IceDevil]

2nd @ 30 (in town cruising) seems slightly absurd... Maybe I'm just not used to high r's on two wheels, as I've been on four for waaaaaaay too long.

[ryder rick]

Detonation?

Valve adjustment?

Who knows, I can't hear it from here...

I can say for sure that,
You should not ride it unless you are sure that everything is right,
or you will find out just how fast one can eat itself up.

Jets don't wear out. However the stock low speed jet is often undersized for a motor that has been modified to improve airflow (air filter / exhaust).

[AustinXL]

I usually shift to 3rd around 40 if I'm riding normal if that helps.

[AustinXL]

Just re-read the post and totally missed the part about stones in a can before! Sounds like it could be detonation?

[(WI)IceDevil]

Hmm. I definitely don't know enough to diagnose and/or fix this problem.. kinda' discouraging given the cost of labor these days. I s'pose.. ya gotta start learning somewhere.

I'm sure that, given my luck, when this ship comes in.. I'll be at the airport.

Thanks guys.

[IronMick]

Originally Posted by (WI)IceDevil

... I'm getting some strange noises when cruising in the mid-range. It's not a pop or a backfire, more like the sound of someone shaking a few stones in a metal watering can. It seems like the sound is coming out the pipes, as opposed to from the motor. Only happens in 3rd gear @ ~30 mph and more noticeable in 4th @ ~40-50 mph. Any ideas? ...

You may be going too slow to be using those gears? Maybe lugging the engine?

Do this, from the Technical Stickys ...

IronHead Noise - Using a Stethoscope
http://xlforum.net/vbportal/forums/s...d.php?t=832376

[sportsterdoc]

30 MPH in third is good if you are downhill and the throttle only cracked.
Harleys have great low end torque, but still do not like being lugged.
+1 to IronMick's comments.

[(WI)IceDevil]

Speeds noted. Thanks.

I'll get on that, Mick. Thanks.

Being green, wet behind the ears, noob etc. sure is exciting. Hopefully, it isn't too costly.

[2007Low]

How about maybe your license plate bracket, rear fender or chain guard rattling. My chain guard was making a rattling sound, it was cracked and after getting it welded, noise was gone.