Unlocking Hidden Horsepower

[SB107]

I am wondering what ideas people have that would help squeeze the maximum amount of wheel horsepower out of a build. A few examples I have heard are: high flow oil filter (less power required to pump oil), gear drive cams, roller rockers.

This doesnt have to be just motor related, it can be driveline related as well. I am just looking to leave as little on the table as possible.

What are some ways you would maximize the straight line performance on your ride?

[jamminhd2000]

There are so many dyno tuners out there that claim to be the best....buyer beware...research your dyno tune guy....talk to people who have used their dyno services...I beleive there is a section here on htt that gives you a list to prepare before hitting the dyno....jimmy

[jamminhd2000]

https://harleytechtalk.com/htt/index.php/topic,35334.0.html

[Hossamania]

Are we talking race motor or street bike?
Ceramic wheel bearings will reduce a lot of parasitic drag. Run light oil in the motor, tranny, primary. Maybe none in the primary if a true 1/4 mile drag bike. Gear drive cams.
Need a few more details on the intended riding conditions. What type of bike?

[rigidthumper]

Drag strip kind of straight line performance? Put those ceramic wheel bearings in Carbon Fiber wheels. Lose weight anywhere you can without sacrificing safety (drilling frame to reduce weight makes sense until it folds up on ya ).

[Hossamania]

Turbo, supercharger, nitrous, all kinds of ways to squeeze maximum horsepower.
Custom made titanium exhaust, tested and modified with Dyno testing to verify results.
Aluminum or titanium replacing everything made of steel that can safely be replaced, including the frame.

[Hossamania]

What kind of budget are we talking about?
There was a no replacement for displacement. Except maybe the three power adders listed above.

[ThumperDeuce]

Decrease rotational mass.

[PoorUB]

Buy something with more performance potential to start with!

[chaos901]

Buy something with more performance potential to start with!

Now that's not "hidden HP", that would be real HP. 

[jmorton10]

Turbo, supercharger, nitrous, all kinds of ways to squeeze maximum horsepower.

I've run all three of these options at various points over the years.  Nitrous is definitely the best bang for the buck of these three options......

~John

[SixShooter14]

I don't know how heavy you are. But many times losing rider weight can greatly improve performance without much wrenching.

[Hossamania]

I don't know how heavy you are. But many times losing rider weight can greatly improve performance without much wrenching.

Speaking from personal experience, it's easier to buy horsepower...

[guido4198]

I don't know how heavy you are. But many times losing rider weight can greatly improve performance without much wrenching.

I had a buddy many years ago who decided to build a Harley drag bike and get on the "All-Harley Drag" circuit.
This guy bought ALL the best pieces and parts from all the best shops. Carbon fiber, ceramics, super hi-tech stuff from all over. He quoted some costs to his old lady once for some billet titanium he was having custom fabricated so that (as he explained to her).."he'd be pulling less weight down the track". She promptly told him to get off his fat azz and just lose 20 lbs..

[SB107]

Are we talking race motor or street bike?
Ceramic wheel bearings will reduce a lot of parasitic drag. Run light oil in the motor, tranny, primary. Maybe none in the primary if a true 1/4 mile drag bike. Gear drive cams.
Need a few more details on the intended riding conditions. What type of bike?

Street/Strip Build
2007 Dyna
124"
12:1 Compression
Mutant Motors 110 heads
Mutant Motors custom exhaust
TW68G Cam
HPI 62mm

Future Upgrades:
40 Shot
Stretched Swingarm
R&D Trans
Air Shifter

Overall goal is consistent 10s on 93 pump gas.

Im just looking at things to upgrade while it's apart. It will be mostly street ridden, with weekend trips to the drag strip.

[SB107]

Drag strip kind of straight line performance? Put those ceramic wheel bearings in Carbon Fiber wheels. Lose weight anywhere you can without sacrificing safety (drilling frame to reduce weight makes sense until it folds up on ya ).

Not looking for more performance in the twisties, just looking to get a consistent street/strip bike.

I really want an aluminum +4" Swingarm, possibly drop some weight on the front end as well.

Also I 100% agree about the safety aspect, I want a fun bike not looking to break any records with it.

[SB107]

What kind of budget are we talking about?
There was a no replacement for displacement. Except maybe the three power adders listed above.

5k is about where I would like to draw the line this time around. Already dumping plenty into the motor and driveline build.

[SB107]

I don't know how heavy you are. But many times losing rider weight can greatly improve performance without much wrenching.

Working on that too. Currently 230lbs, down from 290lbs in January, Hoping for under 200 by spring.

[rigidthumper]

Pingle shifter. Bandit clutch. Busa forks. Shinko stealth tire.
Practice

[PoorUB]

What kind of budget are we talking about?
There was a no replacement for displacement. Except maybe the three power adders listed above.

5k is about where I would like to draw the line this time around.

5K? more of a starting point!

[PoorUB]

Are we talking race motor or street bike?
Ceramic wheel bearings will reduce a lot of parasitic drag. Run light oil in the motor, tranny, primary. Maybe none in the primary if a true 1/4 mile drag bike. Gear drive cams.
Need a few more details on the intended riding conditions. What type of bike?

Street/Strip Build
2007 Dyna
124"
12:1 Compression
Mutant Motors 110 heads
Mutant Motors custom exhaust
TW68G Cam
HPI 62mm

Future Upgrades:
40 Shot
Stretched Swingarm
R&D Trans
Air Shifter

Overall goal is consistent 10s on 93 pump gas.

Im just looking at things to upgrade while it's apart. It will be mostly street ridden, with weekend trips to the drag strip.

No crankshaft upgrade?

If I was going 124" and knowing it was going to get beat on at the track often I would be looking over the $&$ catalog.

Another reason I think you $5k "line in the sand" is low.

[FXDBI]

Blue print the engine has you build it!   Bob

[JW113]

Unlocking Hidden Horsepower. I think I've seen at least two dozen books with that same title.

-JW

[Hossamania]

Ray (No Cents) uses ceramic wheel bearings and said the bike rolls much easier, and when a wheel is spun, it actually keeps spinning rather than just stopping after a turn or two. Pretty cheap find of hidden horsepower. Every little piece counts.
A story in that regard: a friend of mine got his kid into go kart racing, and started researching just like you, to find hidden horsepower. He learned that the wheel bearings with grease in them would stop spinning after a couple revolutions. But if the grease was cleaned out, and they were lubed with Tri Flow, they would spin 20 or more revolutions, not a long term fix, but the bearings would last plenty long for the length of a race, he would just relube them before every race. It wasn't a huge improvement, but it allowed the kart to roll so much better, taking maybe a few tenths of a second or more off per lap. Not a lot of time, but it adds up to a few seconds at the end of ten laps.
At the beginning of the year, his kid ran dead last or close to it, of course. By the end of the year, his kid was running up front and had even won a race. The next three years he took the championships.
A mother came up to him and told him they cheat, that's why by they win. He says, interesting. We came out here yesterday and practiced all day, used up a brand new set of tires, changing air pressures, practicing different lines thru corners, changing Jets in the carberator, and keeping detailed notes on what worked and what didn't. Funny, we haven't seen you or your kid out here practicing all year. So if that's cheating, yes, we cheat.

[SB107]

What kind of budget are we talking about?
There was a no replacement for displacement. Except maybe the three power adders listed above.

5k is about where I would like to draw the line this time around.

5K? more of a starting point!

I already will have 15k+ into the motor and drivetrain.