Back on the road

[Spritz57]

I just finished rebuilding the engine on my '91 FLHS. It's amazing how the characteristics of the engine have changed. The sound and response which I have become familiar with over the years are gone. It's like riding a new bike. The skin on my knuckles is growing back too!

For those interested the repair/modifications were:
Branch/Flowmetric heads were re-machined, valve job, seals, etc.
New Cylinders, Pistons, Rings, and Cometic Gaskets (cometic gaskets raised the compression a few tenths).
New Cam (EV-46) from EV-3, Seal, Bearings, S&S Reed Valve--no more nylon breather valve and Umbrella valve on the breather line.
Rebuilt the Mikuni Carb and replaced the intake manifold with a Screamin' Eagle
Supertrapp 2:1 exhaust system with racing copper gaskets replaced the Supertrapp slip-ons and stock manifold.
The Screamin' Eagle gaskets which were replaced though they sealed well actually pinched the enlarged exhaust ports which caused a carbon build up inside the heads--that cost hp.
Replaced the stock charging system--new stator and voltage regulator (went from 32-38 amps)

Haven't dyno'd the bike yet. It used to make 81 hp (stock hp was 38) at the rear wheel with the old set up. It should improve 5-10% when everything is properly sealed, seated, and dialed in (jetting, exhaust discs).

Got the bike repainted too--had to replace the gas tank and the price was for the additional fender was not cost prohibitive so now everything matches.

I've been babying it for the first 500 and haven't broken 50 mph but life on the local roads plain sucks.

[JustABozoOnThisBus]

1. Sounds like a super rebuild job

That's a lot of work, but your timing is terrible. This is the time of year to start bike projects, not finish them, right?
:rofl:

Anyway, it should run great. I hear you about the skinned knuckles. I think I have a permanent odor of gas and oil.

Many theories on the way to break in a new (or rebuilt) motor:
http://motorcycles.suite101.com/article.cfm/engine_breakin_controversy

:hi:

[Spritz57]

2. My timing wasn't bad, the head gasket's failure was!

Riding season? There is only one riding season, Jan.-Dec. :rofl: (Back at ya')
I only take breaks when the snow accumulates. Wider Products Rock!

Thanks for the link!
:toast:

Gas and Oil smell like victory!:hi:

[flamin lib]

5. The method described in the article is the best way to

"break in" an engine. There is no need to "baby" a new engine. There is only one metal to metal contact and that is the piston ring to cylinder wall contact. If there are is any other metal to metal contact you'll be able to see them right away--they'll be on display under the bike.

The idea is to load the ring to cylinder contact as heavily as possible and that is done by applying power over a wide range of rpm. Accelerate from 30-60 and then coast back down. Repeat for the first 30 miles or so. There! all done with the break in.

Only caveat is to warm up the engine first and don't lug it or over-rev it. Use the lower part of the power range to seat the rings and accelerate smoothly.

I spent nine years as a general line mechanic and re-built a bunch of car engines.

[Spritz57]

7. Thanks for the information and expertise.

[ThomWV]

3. Got a picture or two?

I admit, I had to go look. I would imagine you will have that 500 miles on it by noon today. Do you plan to change the fluids at that point or are you going to let it get a few more miles before giving it fresh oil/grease? When are you going to crank it up and let it pull - which I have to imagine will be quite a pleasure?

Let's see some pictures!

[Spritz57]

4. Changed the fluids after the first approximately 20 miles.

Will change them again at 500--I'll probably change the oil to synthetic at this point since every seal and gasket has been replaced. I have cranked it (oh yeah) up but have not maintained high speeds for any extended period of time. The consensus, of my garage and professional motorcycle mechanic friends, was to vary the speed and not maintain any speed (especially highway) for the first 500 miles--they, to a person, feared glazing of the cylinder walls. Good news is so far everything appears to have been torqued properly--no leaks. As to the pulling power, this new cam actually has a lower rpm torque band and it increases static compression. The acceleration has been better than with the old cam especially in the ranges where I ride on the street. I can feel the bike lifting in the mid 2k's as the power really comes on. I think this will save me a fortune in Dentist bills because it loosens the plaque around my teeth.

As to posting pics, if you can tell me how to do this with this new Mac, I'll be glad to show it off.B-)

As to making 500 by noon, probably not, my professional life and my recreational life are in a constant tension. But by Monday, I'll be there. With the roads around here, I'm encircled by state and federal highways, I have to be creative in my travels and after 30 years in the saddle, local roads are simply not my choice of egress (too many minivans with cell phone talking drivers and young drivers trying to make their bones).

[guitar man]

6. congrats on the good rebuild

I'm contemplating whether to tear my Sportster down this winter and do the top end or whether to run it another year. I really want to go up to 1250cc with it, but I have a hard time justifying tearing down an engine that runs as good as it does.

When I want to post pics, I go to www.tinypic.com . You can upload pics straight to their server and just post the link in your post. :hi:

[Spritz57]

8. I'll take some new pics and post next week, thanks for the link!

:hi:

[Spritz57]

9. Pic Posted

Bought it new in August of 1991.

[guitar man]

10. that's a sweet looking ride!

:thumbsup: :hi:

[ThomWV]

11. Oh, Hell Yes!

Sweeeeeeet!