Not much. Your knees are closer together on the slimline, which makes for a more comfortable ride.
The frame rails on a wideline come straight back from under the tank to form the rails under the seat. On a slimline the rails pull in closer together at the back of the tank, so the seat area at the front is narrower. Most of the rest of the frame is the same, although there were lots of little differences over the years.
Thanks for the answer on frames. I'd like tosee a picture or a real one(s) somewhere. I ride a 74 Norton . Would it be similar to either one?
My son rides BSA and is thinking of "building' a Triton so the question of frame is in that regard.
A commando is exactically that....an isolastic frame circa 68-75
A 54-68 approx featherbed is PRE commando, whether wideline or slimline.
IMO the desireability of a triton is usually among triumph owners that want a better frame. However, I can't see the logic of taking the norton engine out to put a triumph engine in.
To me the norton engine is the HEMI of the british engines. Not that I am biased in any way.....
Dyno Dave wrote:
'However, I can't see the logic of taking the norton engine out to put a triumph engine in.
To me the norton engine is the HEMI of the british engines.'
Glad to see I am not the only one who thinks this way.
This frame thing has always confused me. Does the slimline predate the wideline? Is there a general crossover date of manufacture?
Or is it just a complete mess.
Does the Atlas have a wideline?
The wideline was the original and was found to be a bit wide for comfort reasons.
The slimline came out around 60 I think. All Atlas'(therefore 62+) are slimline.
There was a special norton racing frame, the lowboy, which may be what Mick Hemmings is repopping. It is supposed to be slightly more compact featherbed style. This lowboy may be the manx type high alloy steel frame. This is all low volumne stuff and I have no particular knowledge or exact details.
Thanks for the info. I have ridden Triumph for 30 years and I like my engine in its on frame because I like things like they are supposed to be.My Norton came to me when the guy I as restoring it for ran out of money and interest (imagine that) and sold it to me at a price I couldn't refuse. Iam on my third year ridding it and like it just fine. Almost had a catastrophe last Sunday tho. I stopped at a corner and after a loud metal crunch which stalled the motor I looked down the left side at a growing pool of oil from the primary drive case which was sprung open at the front edge. The wavey washer under the nut that holds the magnet and final drive sproket on must have broke allowing the nut to back off and the resulting crunch. I know I torqued it correctly but my lesson is (and I know ) don't reuse critcal fasteners. Kudos to the nice people who stopped there cars to help in the boonies far from home especially the one who let me use her tools to fix my problem. She offered cell phone an to take my bike home if necassary in her trailer.( 24 years ago her fiance died on his bike on his way to see her on a foggy nght going to fast and hit a steer) Chaincase is OK I put the nut on no washer (and she even had oil) and drove home fingers crossed .BUT darts to the Half Dozen bikers who just roared on by!!!! I always stop and some have used my shop. Be careful who you stop for but a guy riding with his wife i am sure is less of a threat. I am sorry I had nothing to clean up the oil that everyone kept driving through .
Jerry (I am a logged member but somehow never get logged in right)
#8. "RE: self disassembling parts" In response to Reply # 7
A local NNENO guy had a similar thing happen last summer.
Alternator nut came loose and it punched a hole in the primary.
welded cover a few new bits and he was OK.
Lucky guy...he didn't take out the crank end.
As far as I can tell, it does seem to be a rarity rather than a common thing.
#9. "RE: Featherbed Frame" In response to Reply # 8
Tried to write a reply to this a while ago but got firewall problems . Hope this works.
This site from the UK Norton owners club http://www.nortonownersclub.org/
in the History 1940 to 1958 section has information on the featherbed frame. Dave is correct. The slim line turned up in the early 1960s and all Atlases should have it. Evidently Rex McCandless who designed the original featherbed frame didnt think much of it. It was done to made the width across the riders knees narrower. Some people say it isnt as good for racing but Mike Hemmings says he cannot tell the diference. All the earlier frames are called widelines
The first featherbed frames in the 1950s also had bolt up rear sections (until about 1954?) which a lot of people weld up for racing.
It is really important on all featherbeds that the top engine steady which goes from the steering head back to the motor and is bolted to the top fram cross member is always kept tight otherwise the frame cracks where it is welded to the steering head.
The low boy frame was I beleived developed at the end of the 1950s and early 60s for the Domiracer which had the 500 twin motor and was for a time being considered as a replacement for the Manx.(Doug Hele developed)
There are also some very special other frames scattered through the 50s eg the kneeler which was ridden by Ray Amm. You can find stories about these bikes in magazines like Classic Racer http://www.classicracer.com/