I've just had my 2008 fxdf stage 1 tuned and its top speed is only 110mph,
is this about right or should it be able to pull 120? it doesn't seem right to me at all considering they market the top speed as 115 from stock!

its got A Kuryakyn corsair air cleaner, V&H SS and XiED leads for the fueling.

 

Gee Wizz, I wouldn't even try to ride my WGlide that fast. Put yours on a Dyno to find out for sure. My rev limiter is set at 6200 so someone with a math degree can figure out what that equals in speed.

 

not sure about your bike, but my 2010 Dyna FXD is Stage 1 and I hit sixth gear about 70 and I have run up to 90 passing trucks and it has lots more RPMs to go. Never got past 90 or 95 yet. Don't really need to.

 

my 99 fxdx is stage 1 and it weill burry the needle at 120 and still has a little bit to go..maybe 125

dont aske me how i know that...because the speed limit is only 65 here..lol

 

lol speed limits, I thought they were just a suggestion?

so you reckon I should dyno it?
will my weight have anything to do with top speed? I weigh about 25stone, dont know what that is in American money but its big

 

I had my Wide Glide doing about 110. Dont think i could have got much more. Maybe a little but not much.

 

350 Lbs.? I think that's the reason your top speed is lagging.

 

I thought weight just slowed top speed not lowered it?

 

There could be an aerodynamic problem, too.

 

Its down to aerodynamics. A a big bike with a person sat bolt upright will not go quickly compared to a 'crotch rocket' of the same power output.

To get to 110mph with a sportsbike you would need about 40hp which any 250 4 stroke should manage. Much less than our Harleys.

The rev limit is most probably irrelevent since a Harley will not make max power at 6200 rpm.