Another 650 SS thread !

[Fast Eddie]

As others have stated, a 650ss from the 60s isn't ever going to compare with today's Manx on a racetrack. But then I suppose today's Manx racebike is pretty anemic compared with a modern 600cc racebike.
It is of historical interest only that the early 60s 650ss in racing form did well when raced against the early 60s Manx.

Converted for road use though , I imagine a Manx is going to be pretty sluggish getting going.

The 650ss isn't!
This is a fairly relaxed roll on thru first and second to 75 mph. It can be shifted much faster when under duress!
Still, the timer shows the roll on at 8 seconds and off at 14. That is 6 seconds to go from 15 mph to 75 mph. I'm not sure the 850 Commando will do any better, nor will the Rapide 1000. The Rapide might even be slower at this. It's a slow shifting gearbox.
The BSA Super Rocket takes more like 12 or 14 seconds to manage this.

That’s right, a modern Manx would be pretty anaemic against a modern 600 sports bike.

Great point.

Really sums it up.

 

[worntorn]

Only intended as part of discussion, no summation.

 

[baz]

I tried roughing the plates up with stick on emery on the milling table. Is that the same as decking?
When run dry that fix held for a few goes then the slipping started again.
I tried quite a few different things with that clutch before giving in to the BNR plan . The final straw was the continued primary cover leakage after trying all the known remedies.

The BNR kit killed both birds plus it's very light rotating weight seems a good thing.

Glen

What I refer to as "hand decking" is emery paper or similar on a surface plate or and rotate in a figure of 8 until flat
Particularly with new plates
But not creating a rough surface
Just getting everything completely flat has worked for me
The B44 is a little easier because you can run ATF oil
Unlike the b50 that shares the engine oil
I found that once the plates were completely flat I could back clutch springs off

 

[t ingermanson]

Only intended as part of discussion, no summation.

You've got some lovely motorbikes, Glen.

I completely agree about the 60s apples to 60s apples comparison, and I fully stand behind making a 650SS "race bike" that makes zero sense at all, with no justification, other than it pleases the person doing it.

 

[worntorn]

Thanks very much.
I really like the old ss and was a bit chuffed to read another bit about how well they fared in racing way back when. Just a bit of nostalgia, which is a big part of the allure of any vintage bike.
In some cases that is the only allure!
With the SS you get some nostalgia and a really nice handling roadbike as well.

I almost sold my 650SS two weeks ago, then came to my senses.
One of our daughters, at age 41, is having her first baby . She and her fellow could use a bit of help so I said I would sell the 650ss and give them the funds. I haven't ridden it in quite awhile, but then I haven't ridden much at all since getting injured by a big nasty cow.
I offered the 650ss to a friend who had shown interest before. He was very interested, but he is motorcycle rich and cash poor right now. He was mulling selling a nice 650 Bonnie to buy the Norton. He has quite a few bikes, maybe a dozen or so including 4 Vincent twins.
As he pondered the deal I went thru premature seller's remorse and then after a few days changed my mind.

We'll dig into the savings instead.
At 69 I'm probably not going to find another good 650 ss in my lifetime. I don't think very many came to Canada.

Glen

 

[norton bob]

I think the UK and Australia got most of the 650SS bikes . I have a friend who has 3 or 4 ! . Mine is an unknown entity as i have not had it running. Have been told it was "a fast bike " . It will need to be a lot better than my 99 to see any use as the PR riding position and unproven mechanics will put me off. The 99 has an over 100MPH performance and my riding companion has to wind his modern Triumph Thruxton up to stay in touch. My memory of riding an SS in 1963 was of surging acceleration and an eagerness to answer to the throttle .

 

[worntorn]

The 650ss feels like it has about twice as much power at the back wheel as the 99 does. A clubmate had a 99 rebuilt and restored by a very skilled motorcycle mechanic and tuner. This is just a regular 99, not an SS.
We had read about 100 mph top speeds for the 99 and expected that or close to it. I don't know what the top speed was but I'm sure it was a lot less than 100 for that one.
The bike ran well but the power output was sad, noticeably weaker than my BSA Super Rocket, which I find to be a slow bike for today's traffic.
We spent a day riding out in the Valley here and swapped bikes for awhile. Talk about night and day performance!
That 99 felt like my old Honda 90!
After riding the 650ss the 99 owner offered to do a straight trade. He seemed to think that was some sort of a good deal for me! I had zero interest in that deal.
The 99 would be parked in the shop and never ridden whereas the 650ss does get ridden and is a lot of fun.
The 650ss has plenty of passing power, that's what I like. Handling is the same as the 99, which is excellent.

On the 99 you could only pass if there was a very long straight with nothing coming. I found that 99 to be more vibratory than the 650ss, perhaps because I had to really ring its neck just to get a bit out of it. Later on the owner geared the bike up to dampen the vibes but that made the acceleration even more lacklustre.

You are going to be very happy with that 650ss.

Glen

 

[norton bob]

I am building it as a bike to display , If it turns out to be a really good riding experience I will convert it back to a std bike which is much more suitable for our "B" roads . Round here the A roads are full of Daft cagers and motorways are stacked with 100 mph delivery vans , lorries and loons texting on mobiles at 80 mph. I still cant imagine the PR SS will be anywhere as good as the 99 for the conditions . Easy first kick starting , slow reliable idle , ability to carry rain gear, tools, compressor, fuel transfer pump and 6 bottles of iced beer . at 70 mpg. And it leads the rideouts with me holding it back . Some Nortons are slugs and some have snap and crackle , was always so.

 

[Fast Eddie]

You've got some lovely motorbikes, Glen.

I completely agree about the 60s apples to 60s apples comparison, and I fully stand behind making a 650SS "race bike" that makes zero sense at all, with no justification, other than it pleases the person doing it.

Damned right. I’m a huge fan of doing shit simply because you want to. In fact, thinking about it, there’s not really any other way to justify any of the bikes in my shed !

The conversation took a turn into the unavailability of race classes that would favour a 650 twin today, hence the talk about other historic race bikes and their capability TODAY.

However, building a sweet, fast, tuned as you like, 650 because you WANT TO is another matter entirely !

I could get drawn in myself, the idea of JS ultra light pistons and rods, carefully reworked head, lightweight flywheel, dynamically balanced… perhaps a 5 speed box to help keep it all on song… sounds like great fun to me.

My first Triton was a highly tuned 650 with a close 4 speed box. Hugely impractical, but use that close box to keep it in the 6 to 7k range and it was a blast. With the kind of things on offer today for Norton builds, a 650 Norton would be far more fun. Dare I say, ‘advanced’ !

But I digress… those are my fantasies, not yours…

 

[worntorn]

Falloon's Favourites: Norton 650 SS – INFO MOTO

The Norton 650 SS remains the definitive sporting Norton twin. Combining the legendary Featherbed frame with a classic 650cc twin.

infomoto.com.au

 

[jan nelder]

mind you, The Enfield racing flat tracker twin engine has over 90 hp with simple mods from the road model, so in Manx running gear, would make a modern 650SS substitute…..

 

[worntorn]

Those must be some mods ! The modded RE I recently read about used an 865 kit with hot cam, special head, bigger throttle bodies and many more modifications. Cost was horrendous and the power output on dyno test was about the same as a stock 850 Commando or a bit less than a common 865 Triumph.
The claimed increase was much higher.

Anyway, there is something intriguing about an old bike that has good zip and decent handling.

Glen

 

[jan nelder]

Those must be some mods ! The modded RE I recently read about used an 865 kit with hot cam, special head, bigger throttle bodies and many more modifications. Cost was horrendous and the power output on dyno test was about the same as a stock 850 Commando or a bit less than a common 865 Triumph.
The claimed increase was much higher.

Anyway, there is something intriguing about an old bike that has good zip and decent handling.

Glen

I posted on a different thread in July after talking to the RE development team at Mallory Park, while looking at their flat tracker with Harris frame etc

 

[worntorn]

I read that and also the claim that a couple of simple mods to the 650, increased compression , free flowing airfilter will add 15-20 bhp. It all sounds like sales hype. According to 1963 sales hype, my BSA A10 is supposed to rip up to 116 mph !

The fellow with the modded 865 RE pulled out all the stops, spent a lot of money and got a relatively low bhp bike with low quality cycle parts when all was said and done. His verdict was "Don't bother"
It sounds like that RE 650 is best enjoyed more or less as delivered. As a modern 45 hp reliable retro bike, it's supposed to be quite a good machine, but not fast. His dyno numbers are DIN, so theoretical metric horsepower at crankshaft.

Glen

 

[annajeannette]

After reading about the 650 in earlier threads I would like to add some titbits that I picked up. The 1.75 journals were used in the 500 Dommyracer and in the aborted Unified twins before the SS or Manxman. I had understood there were only 2 Unified complete engines Built back in the day , AJD writes there were 6 bikes , Would like to know where she found that info. I am personally familiar with the two current reconstructions which run really well. I understood that the Lawton 650 was seized up by the works rider before delivery and had to have another barrel to replace the one with out of parralel bores . The Lawton bike was reported destroyed in the museum fire , but perhaps it just dissapeared !. I am Currently building a tribute SS producton racer so any information or photos of the Thruxton 650 bikes would be very helpfull.

hello well if you had of read my threads right I did say there were six engines built not six bikes and the Norton 650s all started in late october of 1960 but its was not until november 7th the first batch of 30 was built and Norton built them in small batches has they had to let the parts people chatch up has 80% of parts were made in house along with the Norton Manxman exhuasts and the one off silencers , now as for the experiment 500 domiraces there crank diamiter was 1.60 and not 1.75 and these motors had longer push rods and shorter bucket cam follower and needel roller cam bearing and gas flowded cylinder heads fitted with bronze valve guids the carburetors were amal gp10 with remote float blow but the Norton manxman 650s were being raced out of the box at daytona beach and pebble beach in califonia by Hienze Cragler new jersey berliner motors engineer and berliners motos were the sponser and that was back in march of 1961 well before Sid lawton bike did in 1962 for the thruxton 24 hour race witch a norton 650 won that with 1 minute and 20 second before the next bike witch was a triumph bonnie then third was a Norton model 88