Safe redline for M8

[joepenoso]

Hello  0:
            Safe redline for M8.
            Stock is 5,000rpm.
            How much before it rips?
6,000rpm??
joepenoso

[Rockout Rocker Products]

That's kinda asking someone to be personally responsible for your bike.

A better question might be "How high do you guys rev your M8s?"

[guydoc77]

Built motor?
How built?
Hard to give a single answer.
Stock bike isn't making any more power after 5Kish anyway so doesn't matter really.

[kd]

Well I do know you won't be going where member jbroski goes.     I assume you are talking street and touring use?

[FLSTFIDave]

Mines making power to 5750 RPM.  Don't run it up that high very often at all.

[Clayton24]

Harley advertises 6200 rpm with their power cam and tuner . More so depends on the build cam etc .

[HogMike]

Mines making power to 5750 RPM.  Don't run it up that high very often at all.

My HP starts dropping down slowly about 5500, TQ starts down about 5000 and my limiter is set for 6100
I'll run it close to 5000 sometimes but really don't need to, it has plenty of passing power.
It's a 900LB boat WITHOUT us on it!!!

JME

[Cvosjoe]

My short stroke M8 peaks around 6200. Typically shift about 5500 to 6000 when horsing around. Shifted at 6500 once but took every tooth off 3rd and 4th gear.

[HogMike]

My short stroke M8 peaks around 6200. Typically shift about 5500 to 6000 when horsing around. Shifted at 6500 once but took every tooth off 3rd and 4th gear.

I feel your pain!
Happened to me also.
This was my cure:

[ziggy24]

How do you like the grudge box? Noise? gear ratios? Being that 6th is an overdrive, and now 5th gear is the old 6th gear how much more speed do you need before getting into 6th and staying there?

[HogMike]

How do you like the grudge box? Noise? gear ratios? Being that 6th is an overdrive, and now 5th gear is the old 6th gear how much more speed do you need before getting into 6th and staying there?

Little more noisy in 1-3, but a "nice" gear whine.
I'm shifting later than the others group riding, solo is no problem.
I usually do 6th about 70 depending on the grade, shift down when I give more throttle.

Just got back from Reno where I got 40-51 mpg, group riding, mostly speed limit. Drops to 36+/- mpg when I "play". Decent gas mileage with a big motor IMO.

Mainly got the gearbox instead of rebuilding my stock box, one an done!

JMHO

[kd]

Mike, my GrudgeBox has become more quiet than my new OEM 6 spd transmission was.  The GrudgeBox 6th gear is a only a 250 RPM change so it isn't significant.  You can always drop a tooth on the trans pulley to 31 if you are concerned about the overdrive ration being too high.

[HogMike]

I actually like the overdrive for my type of rides. When I'm with the club rides I'll use 5th (1-1) like their 6th (1-1). I've only got about 3000 miles on the new trans and am getting used to it.

I have a OD6 on my evo that probably has 60 k miles on it and shifts like butter. I haven't compared gear ratios in the evo vs my M8.
That being said, my evo pulls much harder through the gears than my built M8.
Little more HP in my M8, but the evo is 200-300 lbs lighter and likes to rev more.
Two totally different bikes .

[JSD]

Hopped up usually on dyno HP pulls, 6500 rpm