Go Back   Harley Davidson Forums > General Harley Davidson Forums > General Harley Davidson Chat
Sign in using an external account
Register Forgot Password?
Search


General Harley Davidson Chat Forum to discuss general Harley Davidson issues, topics, and experiences.
Sponsored by: J&P Cycles

Reply
 
 
 
P
 
Thread Tools Search this Thread
  #1  
Old 01-19-2007, 04:05 PM
jbnl163's Avatar
jbnl163 jbnl163 is offline
Outstanding HDF Member
Join Date: Nov 2006
Location: CA
Posts: 2,113
Default EVo vs. Twin cam

[sm=biker2.gif]What are the main differences besides displacement between the older but hugely popular Evolution motor and the Twin cam 88"? Can you still get an EVO from Harley? ( If this is a dumb question, forgive me, I am a converted Crotch Rocket jockey.)
__________________

BKD in CA 08' Ultra Classic
Rhineharts

http://www.highwayadventure.com/
Reply With Quote
  #2  
Old 01-19-2007, 04:10 PM
1200c 1200c is offline
Road Warrior
Join Date: Jun 2005
Posts: 1,334
Default RE: EVo vs. Twin cam

There are many. The shape of the combustion chamber in the heads. The Evo had one cam while the twin cam has two. The Evo used gear driven cams, etc.

And they only way you can get a Evo now is through Harley's remanufacturing program. You can also buy a S&S engine based off the Evo.
Reply With Quote
  #3  
Old 01-19-2007, 04:44 PM
Babs's Avatar
Babs Babs is offline
Outstanding HDF Member
Join Date: Jul 2005
Location: NC
Posts: 2,386
Default RE: EVo vs. Twin cam

The evo was the last high tech carb v-twin from the mo-co before the EPA got a hold of a good thing and made H-D go to the twin cam. The single gear driven cam verses dual chain driven cams is probably the biggest difference. The Evo heads were the correct size for it's displacement.. The stock TC heads are the same size as the evo heads but for a larger displacement. (unconfirmed but from some tech article I read somewhere).. Therefore with a TC, a few good mods to do are, swap out the chain cam drive for an S&S or similar gear drive, and have a good pro do some head work or swap to better suited heads.

When my current engine starts showing it's age, I'm going to tear down, do a top-end big bore with heads, cylinders and cams and a gear cam drive.. Just get it all done at once.

Evo's were bulletproof. TC's haven't earned that reputation yet.

One thing in favor of TC's.. The transmission (FINALLY) attaches directly to the back of the engine case on the softail versions. On Evo's, engine and tranny were attached to the frame, with the primary chain case coupling the two. A lot of torsion going on there.. Now with the TC's, the tranny is "part of" the crank case as one member.. more solid. Primary leaks were common with Evo's because of this.. If out of alignment, the best seals in the world couldn't solve it.. I know from experience.

I'd be willing to bet oil delivery is probably improved on the TC's also.. but that's a suspicion, not verified.\

TC88B's (softails) are also counterbalanced, whereas no evo was counterbalanced, that I'm aware of.. Less vibration for a balanced solid-mount vs non-balanced.. This I can vouch for also. Dyna's and tourbikes don't have the counterbalancing but instead use rubbermounted engines so the vibrations are isolated in theory from the rest of the bike.
__________________
Biltmore Lodge #446, Asheville NC. 32nd Scottish Rite Valley of Asheville
Currently one of them traitors riding a Vic High-Ball.. But still love the forum.
My last Harley
My first love
Make April 15th Just Another Day
Reply With Quote
  #4  
Old 01-19-2007, 04:46 PM
Snobal Snobal is offline
Senior Rider
Join Date: Mar 2006
Location:
Posts: 370
Default RE: EVo vs. Twin cam

Until '93 when HD changed the cam bearings to "improve" the EVO, those suckers were almost bullet proof. Might get a base gasket seep at about 50K, but that was no big deal, and cheap to fix if you really wanted to. All you had to do was change oil, keep water in the battery, and make sure that #$%@ regulator plug at the front left of the engine was tight.

TC88's have those wonderful cam chain tensioners...........Other than some problems with the '99 models, the early ones ran fine. Things appear to have been going down hill since about '04. Still a good bike IMHO. Only rode an '07 once, but it appeared to me to be a good bike, just made some really interesting sounds.
__________________
Do it while you can !
Reply With Quote
  #5  
Old 01-19-2007, 06:40 PM
cj_slowdown cj_slowdown is offline
Road Warrior
Join Date: Aug 2006
Location: S.E.PA
Posts: 1,327
Default RE: EVo vs. Twin cam

Quote:
ORIGINAL: jbnl163

[sm=biker2.gif]What are the main differences besides displacement between the older but hugely popular Evolution motor and the Twin cam 88"? Can you still get an EVO from Harley? ( If this is a dumb question, forgive me, I am a converted Crotch Rocket jockey.)
Lot's of info at this site link below:

http://www.heavydutycycles.com/evotecq.htm

cj

__________________
<a href=http://i114.photobucket.com/albums/n278/cjpic/HD-full-right-HDF.jpg target=_blank>http://i114.photobucket.com/albums/n...-right-HDF.jpg</a>
Reply With Quote
  #6  
Old 01-19-2007, 07:40 PM
jbnl163's Avatar
jbnl163 jbnl163 is offline
Outstanding HDF Member
Join Date: Nov 2006
Location: CA
Posts: 2,113
Default RE: EVo vs. Twin cam

Quote:
ORIGINAL: Babs

The evo was the last high tech carb v-twin from the mo-co before the EPA got a hold of a good thing and made H-D go to the twin cam. The single gear driven cam verses dual chain driven cams is probably the biggest difference. The Evo heads were the correct size for it's displacement.. The stock TC heads are the same size as the evo heads but for a larger displacement. (unconfirmed but from some tech article I read somewhere).. Therefore with a TC, a few good mods to do are, swap out the chain cam drive for an S&amp;S or similar gear drive, and have a good pro do some head work or swap to better suited heads.

When my current engine starts showing it's age, I'm going to tear down, do a top-end big bore with heads, cylinders and cams and a gear cam drive.. Just get it all done at once.

Evo's were bulletproof. TC's haven't earned that reputation yet.

One thing in favor of TC's.. The transmission (FINALLY) attaches directly to the back of the engine case on the softail versions. On Evo's, engine and tranny were attached to the frame, with the primary chain case coupling the two. A lot of torsion going on there.. Now with the TC's, the tranny is "part of" the crank case as one member.. more solid. Primary leaks were common with Evo's because of this.. If out of alignment, the best seals in the world couldn't solve it.. I know from experience.

I'd be willing to bet oil delivery is probably improved on the TC's also.. but that's a suspicion, not verified.\

TC88B's (softails) are also counterbalanced, whereas no evo was counterbalanced, that I'm aware of.. Less vibration for a balanced solid-mount vs non-balanced.. This I can vouch for also. Dyna's and tourbikes don't have the counterbalancing but instead use rubbermounted engines so the vibrations are isolated in theory from the rest of the bike.
Thanks Babs.
__________________

BKD in CA 08' Ultra Classic
Rhineharts

http://www.highwayadventure.com/
Reply With Quote
  #7  
Old 01-19-2007, 08:37 PM
dog155's Avatar
dog155 dog155 is offline
Extreme HDF Member
Join Date: Nov 2006
Location: Windham,Maine
Posts: 12,731
Default RE: EVo vs. Twin cam

It sure would be hard to improve upon an Evo,but the few things Harley in the TC were a big improvement.
__________________
2006 RK 155" R&R TwinCam
2000 Boss Hoss 427" SBC
Reply With Quote
  #8  
Old 01-19-2007, 10:57 PM
Steeltown Steeltown is offline
Senior Rider
Join Date: Jan 2005
Location:
Posts: 385
Default RE: EVo vs. Twin cam

ONe thing that hasn't been mention is that the Evo heads, the surface area, or "squish band" (where air is force into the combustion chamber) area was on only one side of the head, in the TC, it is all around the cumbustion chamber which creates a much higher percentage of burnor efficient burn, and in turn more power...
__________________
www.hawgzone.com
Reply With Quote
  #9  
Old 01-19-2007, 11:09 PM
RandyM1911 RandyM1911 is offline
Senior Rider
Join Date: Sep 2006
Location: The People's Republic of New Jersey
Posts: 400
Default RE: EVo vs. Twin cam

Nicely said Babs. Good, concise description of the major shifts. Kudos.
__________________
http://i121.photobucket.com/albums/o...icture105B.jpg

Democracy is two wolves and a sheep voting on what to have for lunch. Freedom is a well armed sheep contesting the vote.
Reply With Quote
  #10  
Old 01-19-2007, 11:18 PM
FLGEEZ's Avatar
FLGEEZ FLGEEZ is offline
Road Master
Join Date: Sep 2006
Location: NORVA / Pittsboro, IN
Posts: 820
Default RE: EVo vs. Twin cam

One good thing about Harley-Davidson is intra - Brand recognition. Softails, Dynas, Touring, Sportster. All but one share a great deal of engineering. The Sportster is the Odd Bike out. The Evo engine, like the Twin Cam has been modified for each line to suit the Legend of the Line.

And like many folks, I can't address most other lines beyond what I own. Touring, EVO and TC, and pre rubber mounted Sportster. That'a what we own.

The one thing I can vouch for is that as early as 1995 and definitely 1996, The Evo engine in the Touring line did have a mated transmission. No Torque framed mounted issues her. Look up Transmission in any after market vendor site and what you will find is a lot of trannies for Softails, that are not applicable to Touring/FXR's or similar tranny mated machines.

Just my observation. Evo's and TCA, non balanced,ARE different but not all platforms mount, shift or oil bag the same. Lot's of good info in the EVO section and even there not all answers apply to all platforms.
__________________
Retired, not tired, and two tired
Ride like you have the Wind
Ride some, drink some, have a hoot, snore, fart, then rinse and repeat.
Reply With Quote
Old 01-19-2007, 11:18 PM
 
 
 
P
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
GREAT article on Evos vs. twin cam-Enjoy! Brettfullthrottle Evo Classic Models 74 08-29-2014 04:27 AM
Putting an evo fatso in a twin cam frame thebikeshop Evo Classic Models 11 08-16-2014 08:27 PM
Evo in a twin cam frame thebikeshop Off Topic 3 08-16-2014 10:16 AM
Evo or twin cam..Scott...djl Dry509 Engine Mechanical Topics 20 07-07-2014 03:22 PM
Evo or Twin Cam 88 desert drifter General Harley Davidson Chat 26 09-30-2012 01:28 AM


Tags
124, alignment, cam, carb, chaincase, counterbalancing, edelbrock, evo, evolution, freedom, harley, kit, motor, primary, ss, swap, twin


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Forum Jump

Join HDForums

Advertising
Featured Sponsors
Vendor Directory
Sponsors

All times are GMT -5. The time now is 05:15 PM.


Internet Brands, Inc.