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[reo]

Last weekend I was out running with a freind that has a fairly hot bike and we were running wide open comming back home trying to beat the weather. We were up to about 115-117 and I heard the bike hit the rev limeter (I think). I had my bikes mapping re-done last year and I do have the .MTF file. I went in and found the limit is set to 5400, I remember talking to the tuner after first riding it last year asking why he set it so low when the stock file is set to 6200 and he said there is no reason to set it any higher that my bike's power falles off after that point and the b motor is fragile at high r's. I know with the stock cam and heads even with the rineharts the motor's rpm limit is somewhat low but it still makes power and think it should be set higher.

I was wondering what your guys have yours set to. I can go in and play with the mapping just looing for imput.

[factoryphil]

I have mine set at 6200. I would think that shifting at 5400 would put low below the desired rpm for the next gear. Even at 6200, I find myself hitting the rev limiter once and awhile.

[BLM777]

6200 is the standard used by most of the top, experienced dyno tuners.

[erniezap]

6200 as well

[erniezap]

While set at 6200, when I jump on it I still hit the limiter in first gear especially, and the bike is still pulling hard

[JCZ]

While set at 6200, when I jump on it I still hit the limiter in first gear especially, and the bike is still pulling hard

Ernie, when you jump on it, try going for your shift when you see your tach down around 5,500 rpm.  If that doesn't work for you (it means you're sifting too slow [smiley=huepfenlol2.gif]) drop down to 52 or 53 hundred.  If you hit your rev limiter, you're probably gonna loose the race.  JMHO

[sefatboyscott]

I used to hit the limiter in the first 3 gears, I tend to shift at around 5,400 to 5,500 rpm. I like to stretch em out, habit form riding rice burners.

Set at 6,200 now.......occasionally hit the limiter still when not paying attention.

[HUBBARD]

Yeah, 'er 'uh, reo,
  Although my dyno sheet reflects 6200 RPM, as a good friend of mine pointed out to me, Neal Taylor reset mine to bump out @ 5800RPM.  Like everyone else, if I do not keep my eyes on the Tach, which is very seldom, I'll hit the limiter in 1st gear, every time.  This is not good.  As an experienced Engine tech. yourself, you know rods do stretch at high RPM's.  I realize the limiter is a cushion for damage, but if one keeps bumping it, especially with a BIG MOTOR, one will have BIG PROBLEMS.  BTW, been takin' any short-cuts around detours lately?  [smiley=huepfenlol2.gif]  Later--HUBBARD      

[Unbalanced]

Reo,

I would rather see your dyno and where your hp / torque intersect to give advice of where your rev limiter should be.  If they intersect at 5400 you might try shifting around 5200 because even if your fast you will most likely hit 5400 rpm and you are going to want to give yourself breathing room with the rev limiter at say 6000 for this example.

Hitting the rev limiter almost asures you of losing the race at hand.   You should look to have the rev limiter for the oops / oh sheet times your not paying attention.  I would base your rev limiter on peak intersection of HP / TQ plus 500 rpm.    

[reo]

Yeah, 'er 'uh, reo,
  Although my dyno sheet reflects 6200 RPM, as a good friend of mine pointed out to me, Neal Taylor reset mine to bump out @ 5800RPM.  Like everyone else, if I do not keep my eyes on the Tach, which is very seldom, I'll hit the limiter in 1st gear, every time.  This is not good.  As an experienced Engine tech. yourself, you know rods do stretch at high RPM's.  I realize the limiter is a cushion for damage, but if one keeps bumping it, especially with a BIG MOTOR, one will have BIG PROBLEMS.  BTW, been takin' any short-cuts around detours lately?  [smiley=huepfenlol2.gif]  Later--HUBBARD      

I rarely hit the limiter when shifting even out of first. I had a pro-gas car years ago that taught me reflex timing in shifting habits. This bike is a dog compared to those days. My concern was hitting the limiter when topped out in fifth gear (I know I need a six speed) Hub you have to translate “been takin’ any short-cuts around detours lately?” or do you know something. Thanks for the input on your limiter settings

Reo,

I would rather see your dyno and where your hp / torque intersect to give advice of where your rev limiter should be.  If they intersect at 5400 you might try shifting around 5200 because even if your fast you will most likely hit 5400 rpm and you are going to want to give yourself breathing room with the rev limiter at say 6000 for this example.

Hitting the rev limiter almost assures you of losing the race at hand.   You should look to have the rev limiter for the oops / oh sheet times your not paying attention.  I would base your rev limiter on peak intersection of HP / TQ plus 500 rpm.    

Thanks Unbalanced, I like your answer on the intersect plus 500, makes sense. I am very familiar with a lot of motors but Harleys are new to me, I know piston speed is one of the biggest handicaps in rpm limits with them. I will try to scan my dyno sheet and post it hear when I get a chance but in response my intersect, it look like 5300 so I will probably go with 5800 to 6000. Btw that was my initial instinct, I was looking for input here and of course I got it thanks again guys.

[Big Time]

Horsepower and torque intersect at 5252 rpms no matter what, correct?

horsepower = rpm x torque / 5252

[HUBBARD]

Yeah, 'er 'uh, reo,
  Didn't you guys have to run over an unpaved section of hi-way, on the way back from Cherokee, when you passed those two idiots that wouldn't get out of the way?  At any rate, I was thinking at 5400RPM in 5th gear, wouldn't you be traveling faster than 115 MPH?  [smiley=nixweiss.gif] Please advise.  Later--HUBBARD

[reo]

Yeah, 'er 'uh, reo,
  Didn't you guys have to run over an unpaved section of hi-way, on the way back from Cherokee, when you passed those two idiots that wouldn't get out of the way?  At any rate, I was thinking at 5400RPM in 5th gear, wouldn't you be traveling faster than 115 MPH?  [smiley=nixweiss.gif] Please advise.  Later--HUBBARD

I will have to check the next time I bring it up under better conditions but I swear I heard the rev limiter when we were out last weekend and I know it topped out at 105mph when riding back with jack and this is before it was remapped since then the rpm turned up. My tack is off, it says 5100 when its 5400 on the .MT5

Maybe your are right on the top speed, when I checked my gps the max speed recorded was 291mph that day I will have to take a pic and post it here later.  

[reo]

Here you go Hub, look at the max speed on the right second from bottom.

[reo]

And here is a scan of my dyno sheet for you Unbalanced,