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[RoadDawg]

Those of you keeping up with the Harley 117 Kit thread know that I recently had a 117 kit installed in my 2014 Breakout. The tech did a 50 mile "break in" on the dyno machine and told me to run it for another 500 miles, keeping it under 3800 rpm, and bring it back for the final dyno tune. Well, after I hit the 500 mile mark, I started for the Harley dealership to drop off the bike. Couldn't resist a quick twist of the throttle, and at about 4300 rpm the bike shuddered so bad it felt like I hit the kill switch. My heart stopped for a second. Scared me. I continued to the shop and the guy tells me the tech set my rev limiter back after the initial dyno tune. Wish somebody had told me. Anyway, my question is how  does a rev limiter work, and could I have damaged anything in the engine? Thought I heard some tapping immediately after, but after a minute or two all sounded normal.

[Road Dad]

Set at a certain rpm it will start cutting out spark (ignition) when reached. No damage done. Just feels weird and sound bad.

Your bike is good!

[Scott7d]

I hit the limiter a time or two on days where I'm riding with my "more aggressive" friends. I'm sure doing this frequently can't be too good, but overall I've had no problems with the bike because of it.

[HUBBARD]

Don Tilley told me constantly "hittin' the chip" was hard on valve springs.  Know where it's set, and change gears before you hit it.  If you hit it in 6th gear, you're definitely haulin' ass!      Later--HUBBARD

[Road Dad]

That would really would not do anything unusual to the valve springs. Over revolutions (above red line) could on the other side do damage to valve train because it's forcing the valve to stay open longer than normal. But with a proper rev limiter that limits spark or fuel flow you should have no issues at all.

[HUBBARD]

I'll stick with what Tilley said.  He had forgotten more than most people know about Harley Engines.  There endeth the lesson.  Later--HUBBARD

[Twolanerider]

4300?  That's awfully low for a rev limit and it is within the range you might need in an "uh oh" moment to quickly get your tail around a truck on a two lane road.  I'd be more than a little upset to find out after the fact that someone set my rev limiter that low and never bothered to tell me.  If in the worst case scenario I've got to choose between some potential but unlikely engine damage and a very real collision I want to be able to twist the grip.

[grc]

4300?  That's awfully low for a rev limit and it is within the range you might need in an "uh oh" moment to quickly get your tail around a truck on a two lane road.  I'd be more than a little upset to find out after the fact that someone set my rev limiter that low and never bothered to tell me.  If in the worst case scenario I've got to choose between some potential but unlikely engine damage and a very real collision I want to be able to twist the grip.

You beat me to it again Don.  I was about to ask the OP why the "tech" set the limiter that low.  From the post it sounds like he had it set higher when he did the tune, then set it lower before giving the bike back to the owner.  That makes absolutely no sense to me unless an owner requests it for some reason.

This is a "B" engine, so it comes with a lower stock rev limiter setting than the "A" non-balanced engines, but I'm not so sure it should be only 4300 rpm.  Any engine builders / tuners out there who care to comment on the appropriate limiter setting for a "B" engine?

Jerry

[RoadDawg]

From the post it sounds like he had it set higher when he did the tune, then set it lower before giving the bike back to the owner.
Jerry

Jerry, you are correct. After a 50 mile break in with the dyno, the tech did this as a safety precaution because he didn't want me to run the bike over 3800 rpm for the next 500 miles before returning for a final dyno tune. I just wish he would have told me he did it. He did tell me not to bring it past 3800 but neglected to mention he lowered the rev limit. Freaked me out when it happened. Thought I blew up the motor!

[Rooster]

Don Tilley told me constantly "hittin' the chip" was hard on valve springs.  Know where it's set, and change gears before you hit it.  If you hit it in 6th gear, you're definitely haulin' ass!      Later--HUBBARD

Does that mean they are still behind you

[Twolanerider]

Jerry, you are correct. After a 50 mile break in with the dyno, the tech did this as a safety precaution because he didn't want me to run the bike over 3800 rpm for the next 500 miles before returning for a final dyno tune. I just wish he would have told me he did it. He did tell me not to bring it past 3800 but neglected to mention he lowered the rev limit. Freaked me out when it happened. Thought I blew up the motor!

The mind just boggles at the potential liability exposure that would come if you ever got ran over by oncoming traffic you would otherwise have been able to get out of the way out of.