Getting more power out of an Evo

[Ridetard]

Looking for opinions here. I own a bone stock 94 EVO which by todays standards is a dog (imho). I want more power but dont want to mortage the farm to do it. Have had serveral suggestions from reliable sorces but seems they all have different views. I was thinking a simple cam change and rejet the carb? Maybe change out the exhaust. Last resort will be to have the heads replaced or reworked. I am looking for another 15 to 20 horsey's and naturally more torque. I dont want a compromise reliability and dont want an obnoxious thundering bone shaker. The simplier the better. So whats a guy to do? All replys welcome. Thanks

This ad is not displayed to registered and logged-in members. Register your free account today and become a member on HD Forums!

[honestbob]

E.V. 27 cam, Mukuni 42 carb,Crane programable single fire ignition and V.H. 2into1 exhaust. That will light it up.

[cowboy1]

If you want true power out of the evo, don't get HD parts as you don't have a warranty to deal with. Get in touch with Nigel Patrick who is the absolute best motor guru for bikes. http://www.patrick-racing.com/

Set your budget and contact them and they will help you. IMHO and I have done several evo motors, you should at the least do head work, pipes, cam, crane single fire and a mikuni. Patricks will have a pre tuned mikuni for your proposed set up for $450 or so and thats for a polished flat side.

It also depends on what you want to spend. For less than $6,000 or $7,000 you can get a full crate motor with 120+ HP. But for less than $2500 or so you can get close to 95 HP or so.

[Harley_Dude]

Originally Posted by Ridetard

I dont want a compromise reliability and dont want an obnoxious thundering bone shaker. The simplier the better.
Thanks

There within lies the rub, more power = less reliability.

Pull the stocker and get an aftermarket (pick your size) with a warranty. Bigger you go the more stuff you're gonna have to change out, starter, battery, clutch, etc. I'm not a fan of the Korean engines, so I would go with S&S, Ultima or Patrick. Then if you ever what to go back to stock or sell it put the stock engine back in.

Do some research on what your build will cost then compare this to a whole new bike. You can get a Titan, Ironhorse or Big Dog for pennies on the dollar right now. Might be cheaper in the long haul and you've got a second bike.

[ken thompson]

If your bike has been faithful to you for the last 14 years don't go messing with it. If the engine is clapped then that's another thing. If it ain't broke don't fix it.

[cowboy1]

If reliability if key, stay away from Ultima and Revtech. Ultima makes great HP but are notorius for being fickle. Patrick is the best most reliable motor out there but can be expensive. S&S on the other hand is a very good motor, while not the power makers of Patrick, make great HP, easily pumped up and have a great warranty with dealers everywhere. If you are not a wrench, S&S is the way to go. Get the 124 bone stock (doubt your frame can handle it) or better yet, get the 100" square motor with 4"x4" bore and stroke which makes 110HP and 115 Tq. It's a great motor, low compression and runs very smooth cuz it's square. Now the 107 is nice, throw in a 600 cam and a 45 mikuni and you will have great power but keep in mind that S&S's 107 and above, tend to blow compression releases onc ein a while but it's covered by warranty.

[Da Gumpmeister]

NOT knowing ALL of your situation, and what scoot you have, I go with Harley-Dudes suggestion in the middle.
For what it cost to get 'decent' snoose outta a stocker, you can pick up a 107, 113, 120, or 127" Ultima El Bruto. Direct bolt in, ready to run. Spend a day on the puter, find the 'best' deal you can on a 6 spd(they're out there for UNDER a grand, easily), pull the guts outta your 5, put in the 6 spd set (NO PAPERWORK), no clearance issues, same final drive, yadda, yadda.
They are NOT bone shakers, nor maintenance headaches. Good smooth reliable POWER. When Larry first started dealing with these, I thought, right, more after market junk. I know of 2 baggers and a few FX styles, running 'round with these, and they RIDE the chit out of 'em. Neary a problem with the power plants. They eat 'tars', but CAN'T have everything.

BUT you can do the carb, exhaust, ign, and head work route, if'n that'll be more in your $$. But again, to get what I'd consider any decent snoosh (beings I was opening it up), gonna have a chunk o' change in it, anywho. Jus' MFUO, tho.

[cowboy1]

Before you go buying a motor, check into clubchopper.com and see what those guys say as they are true motorheads and will be able to give you the info you need. Once again I DON"T think the ultima, el bruto or not, is what you want. Not as reliable as the S&S. Get your information gathered and think it through before buying a motor, that is if you are going that direction.

As for trannies. You get what you pay for. I would not run anything except a baker for anything with decent HP. Burt makes a bullet proof tranny and guarentees them for 5 years. Make sure you have a decent clutch as well. You can use the stocker primary if you like and if not, I have an S&S billet primary for sale with a good clutch.

I can't say this enough STAY AWAY FROM REVTECH AND BE CAUTIOUS WITH ULTIMA. Another guy you can get in touch with is John at scooters performance in Florida. Feel free to tell him that I said to give him a call. He will be happy to answer your questions and let you know the best direction, in his expert opinion, you should go.

[mp]

Actually, if you read the few magazines that actually test for performance, the Evo was just as fast as the current TC96. But we all need more power than stock, and you're on the right track for a noticeable bump in power by changing the cam, exhaust, and air cleaner. If you can still get a Screamin' Eagle air cleaner for an Evo (with a K&N filter), they're as good and as cheap as any if you order from one of the 20% discount dealers. Otherwise, I'd go with the complete air cleaner and filter from K&N. Good slip-on mufflers like Cycle Shack or Kerker or D&D on the stock headers will make nearly as much power with these mods as anything else, and for a better price.
An Andrews EV13 for more low end, or an EV27 for more power above 3000 rpm would be good reliable choices that won't hurt your fuel mileage much, if any. Be sure to toss the OEM inner cam bearing and use a Torrington B-138 instead. New lifters are a must; the OEM in '94 were weak. Some say the newer style Evo lifters from Harley are OK, and less expensive. I used Crane.
Evo heads flow quite well for OEM, so it's not a necessity to do anything to the heads.
If you don't want to spend money on a Mikuni carb, the CV does very well with some modifications. The http://www.nightrider.com/biketech/hd_cv_mods.htm site covers these very well. In any case, do not use the kits like the Thunder Slide or Dyno- whatever. These make the carb way too rich.
Even with the stock cam, the exhaust, carb and air cleaner improvements will wake up your Evo noticeably; with the cam you'll be smiling enough to have a problem with bugs on your teeth.
One other improvement you might consider for the future; New Progressive fork springs and shocks. Big difference in handling and overall road feel.

[cowboy1]

It seems that different folks have different opinions as to what power from an evo is. If you want powers in the 80's or so then I would do something along the lines of what MP mentioned. but if you want REAL power, you will need to spend money and you need to figure what your goals are as well as what you have to spend, then take it from there. I'm happy that my bagger with the HD stuff done to it is upwards of 100/100 or so but an evo set up correctly can be in the 120/120 easily. My chopper with the set up I had was a 10 second bike...to me thats power.