I want all to know first that I have been working on and riding Harley s for over 40 years none stop. I even do all my own machine work other then on the new pressed cranks but on Evo and older not a problem not much I cannot do. Please unless you are experienced in motor building do not feed me any new bee BS.

OK with that said I want to start to collect parts and get things ready so when my low mileage of 91k miles motor does need redone I will be ready as it is just about my only transportation and will have to be done quickly.

I am not looking for a fast bike but since I run a HD sidecar looking for something with low-end toque and best gas mileage as I can get. I am going to put a 4 3/8 stock Harley crank in it balanced, trued, plugged and welded. The heaver flywheels will help with low end torque which I know helps do to the many past motors I have build mostly Shovel and Evo. All so the longer stroke will help with improving fuel mileage. Many years ago I built my shovel with a 4 ½ inch stroke with a S&S B and if I keep my wrist out of it would get better gas mileage then stock motors.

I will all so have my stock throttle body bored from a 43mm to 48mm. I would like some input on cams that work not cams that say they are low-end torque cams. I have looked at S&S 509 and Andrews TW21 has any one run them in their twin cam or what cams do you recommend? All so a free flowing set of slip on’s that are about as quite as stock mufflers as I like listing to my stereo. I would appreciate any constructive opinion from those that have experience in twin cam motors and have been riding and working on Harley s for more then just a few years.
Thanks
Jeff

 

Using the 4 3/8" crank, and only assuming your going to bore to establish a 103"er, and then assuming the OEM 85cc cylinder head chamber volume, you'll be at 9.6 cr.
That is the dead-on compression, for a no-pms build, with the use of an Andrews 26.
Won't be a big horsepower engine, but it'll have grunt, without issues either.
That'll pull pull that sidecar......... with authority.
Scott

 

From what I have read the Kuryakyn Mellow Crusher Mufflers will give you the performance you want without the exhaust note being loud at all. There are several dyno sheets over on HTT with larger engines and Steve @ GMR Performance reports how well they perform and how how nice n mellow they are.

I may be using them on my 124" exhaust in the future

Here is video of them >>

 

Quiet power = Supertrapp. Period.
Scott

 

No I am going 103 only 96 reason is over my 40 years I have found going bigger on the bore it uses more gas then the longer stroke with smaller or stock bore. Yes I agree the bigger bore will give more torque but my experience less fuel mileage. As stated in my post good gas mileage is just as important as the torque. Which we all so know torque is HP as when you figure HP you do it from using the torque.

As you can see from my signature I am a distance rider so fuel mileage is VERY important.
Thanks

 

Those sound about what I want but is there any VE dyno results on them?
Thanks

 

Do they make slip on's like I said in my first post. If so I need to check them out. As sated I am not looking for all out power. You say you do crank work on twin cam cranks what method or methods do you use to balance and what equipment do you use?
Thanks
Jeff

 

Been hearing a lot of positive buzz and seeing a lot of CFR exhaust ... I think they have slip ons ... only time I heard them, they were a notch above stock noise level, though ...

You might look into them if you're not familiar ...

You didn't indicate what bike you're doing this work on ... I am surmising from the posts so far it is an 88" TC in a Touring model ...?

 

We build, re-build, balance,pre-1999 cranks here in house with all S&S Tooling.
All of our pressed-togethercranks go directly to Darkhorse Crankworks, Newton, Wisconsin.

 

I guess I could have been more clear. It is a 02 Ultra with HD sidecar.
Thanks