Gents-

I just bought an 85 4 spd EVO Softail, my first Harley. I got it out on the HWY and at about 70 mph/3000 RPM the engine is reving down and then back up and then down. I checked it out and in all 4 gears at about 3000 rpm what I assume is therev limiter is kicking in. To my knowledge I don't think the 85 was original with a rev limiter. And if the previous owner installed it isn't 3000 RPM alittle low for the rev limiter to kick in?? I know the older Harleys weren't built to scream but I still think 3000 is a little low. Any advice or info would be great. I would just like a little insight into what's up, and what my options are. I'll post some pics as soon as I figure out how to shrink digital photos. Thanx for any info.

-PIKO

 

Congrats on the bike...it just so happens I bought the same bike new and thinkbetween '84 and '90 itsthe best motor running. The rev limiter was part of the ignition design at 5250 RPM retard. When I got on it, I did notice the retard at higher RPM's but not at 3000. After a few years, I replaced the original design with a "screaming eagle" ignition and cam which gave me better performance. Attached is a web link that will provide more info. Paste the link into your web browser and notice page 209 item "D'.

Not sure why your getting the retard so low...one thing for sure, either the ignition module works or it doesn't. It will not slowly go bad, however the sensor plate will start to act up over theyears due to heat.

http://books.google.com/books?id=NOO...l=en#PPA209,M1

 

Check for vacuum leaks first. That era had the crappy "compliance fittings" intake seals. I used to have to replace them all the time. If you change it out to the later ones, it is much better. After that, check the vacuum switch, but I'm going to say you have an intake leak. With the motor idleing, spraya little carb cleaner around the intake fittings and listen for a change in the engine. Change=leak. Replace compliance rubber pieces.

 

I had a similar problem with my then-stock '89 when I first got it. Solved it by swapping the stock butterfly carb and intake for a used CV and doing away with the compliance fittings etc.

 

with that motor I should be doing 70-80 in 4th without the revlimiter kicking in right?

 

In 4th gear, you should not hit the rev limiter until you are deep in tripple digit speed, if you can hit it at all in 4th.

You most likely have a carburation issue, not a rev limiter.

 

thanx

 

After checking the intake for leaks, then check your main and intermediate jets if it still does it. What you are experiencing is called "Lean Surge." I'm surprised it isn't backfiring through the carb. I used to have to replace those compliance fittings yearly until I got rid of them with the S&S. HD knew there was a problem and replaced them in 87 with the newer system. That was back when they were serious about fixing known issues. I read on the other forums here that they aren't so keen on that anymore (again).

 

I have an 85FXEF.

with a correctly adjusted clutch.

Are you sure that the mystery revving is not caused by improper clutch adjusment or worn fibre plates? I am thinking your clutch is not engaging fully as you get to higher speeds/revs.....

 

Reving up and down sounds more like a "surge", probably lean. Rev limiters sound more like the motor is missing not surging. Look at your carb and manifold.