curious why alot of guys with 88 twinkies bored out to 95 inches are as quick or quicker then most 96 inchers and some 103's?

 

I'm not positive, but I'm guessing that a lot of people that go with the 103's think that the increase in displacement alone is going to give them "tons more", and if they don't get the headwork done, they're not picking up much at all other than a few more cubes. I think that most guys that go the 95 route have the headwork done along with the performance enhancing bump in compression. Not sure, just a guess.

 

Agreed - even with 255 cams in my Limited my 95cu in Fatboy is faster. Of course the lower weight helps - but so does the high comression piston set-up, the heads etc etc . . .

 

Gearing on the 5 speeds might contribute to "quickness".

 

but the dynos don't really lie all the time...its mostly in the horsepower that a 95 incher can be higher, think it has to do with the stroke. so much for there is no replacement for displacement. alot of 95's if done right are over 100hp and 100 torque

 

Alot depends on the mods, and has been stated, gearing. My 95 will outrun 96's and 103's all day long, up to around 85. After that they start catching up. Personally, I think it's because I still have the 3:37's. With 3:15's I'm not sure if I would still have the same jump. I really don't think there's much difference, or I haven't seen any numbers to back up big gains, between a 96 and 103, just on the bb kit alone.

 

I think you have put your finger on it with the lower gearing. If you really want to wake an 88 up Harley does a SE 21T crank sprocket kit, which comes with a shorter chain. With 3.37:1 gearing the bike has a 7% increase in rear wheel torque over one with 3.15:1, but the 21T gives 3.75:1 and a 19% increase over a 3.15:1. I have one on my Dyna and it flies!

 

Good post Leo... my 95" RG I had would flat out smoke anything out there. Ton's of torque and hp and with stock gearing mind you.

 

Gearing other engine mods, aerodynamics all come into play.
A lot about quickness has to do with the rider's weight, and how hard they push their bike.

 

Interesting. Both my 103s are faster than the 95 I had in my RK. But then, my 60ci Suzuki is even faster.