How fast will she go?

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I have always been under the impression that an unfaired 50 BHP Manx Norton is capable of about 130 MPH on the IOM. You probably have 10 BHP more and another 15 lbs to carry. So I'd expect more than 120 MPH with the right gearing and enough room to do it in. An 850 will pull a very high gear - more than you would normally use around town.
 
I took it to the ton in third yesterday. 7200ish RPM. 88F about 75% Humid. If someone was wonder if I was nuts (for doing this anyways), I have Radius cam, BSA lifters and behive springs which gives me a relatively higher redline. All other aspects of bike in good nick (chains, wheels and bearings, gearbox, etc. No weaknesses that i know of. I could have kept going but I did what I set out to do, to experience it.

RGM belt drive @ 1.964:1, 19t sprocket.
Seeing that 50mph in third was 3600, I kinda knew where I was going.

I don't know how fast it will go and I think it might be safe to say that I never will.
 
To be honest, I don't really know how fast my bike is.
When I'm WFO, the speedo needle bounces between 95 and 115 mph. I just split the difference and say it goes 105. :)
 
RGM belt drive @ 1.964:1, 19t sprocket.
Seeing that 50mph in third was 3600, I kinda knew where I was going.

I don't know how fast it will go and I think it might be safe to say that I never will.
Click to expand...

Pete, I have a Norvil belt and 20 tooth countershaft sprocket, Megacycle 5600 cam
and completely rebuilt motor with 20 thou over pistons on my 850

with my dual Amal Premiers I don't have anything left past 110mph, and thats fine with me
 
1up3down said:
RGM belt drive @ 1.964:1, 19t sprocket.
Seeing that 50mph in third was 3600, I kinda knew where I was going.

I don't know how fast it will go and I think it might be safe to say that I never will.
Click to expand...

Pete, I have a Norvil belt and 20 tooth countershaft sprocket, Megacycle 5600 cam
and completely rebuilt motor with 20 thou over pistons on my 850

with my dual Amal Premiers I don't have anything left past 110mph, and thats fine with me
Click to expand...

That seems pretty comparable, an apples and oranges kind of thing.

Ya know, I find 90 easily and comfortably and can cruse at that from time to time, but every mph over that get amazingly crazier and crazier like some hobotian quantum time/space continuum type of thing. I guess I can see going faster but only on a bike made for it. I did 140 once on a 999 by the time I got to the end of a highway entrance ramp, but again, it's relative and like 140mph on a 999 is 95mph on a Norton.

The 999 ride was a promo to take a ride and get a free Tshirt. OK I'm in. The rearview mirrors were useless, the Tshirt was really cheap, but oh what a ride. Their just crotch rockets, not much character. I sold a 750ss to get my Norton. I originally got the 750ss cause I couldn't get a Norton at the time. You know where my heart is.

Just to point out, the third gear ton was amazingly smooth and solid.
 
Why :? Most everyone has a modern bike too that does the ton in 3rd or 4th gear without breathing hard!
 
For what it's worth, not very much no doubt, I used to have a BSA 500 Gold Star with an RRT2 gearbox (close ratio) that would do about 75mph in 1st, 85/90 in 2nd, 100ish in 3rd and 110/115 in top, with full road equipment, in 1967/68.
cheers
wakeup
 
grandpaul said:
pete.v said:
like some hobotian quantum time/space continuum type of thing.
Click to expand...

Now THERE is a quote!
Click to expand...

Paul
I looked into that very question, spoke to this guy, a bit of a petrol head as it happens.
How fast will she go?

He says hobot is correct and in fact he understands every word steve says on commandos and that the problem lies with your grade of knowledge in all things quantum. That's what he said!
 
How ya know Dr. Williamson knows enough Commando physics to double check hobot entanglement? Pretty risky public statement Paul. He'd have to be following a long time with close attention for such a conclusion. Anyway fast is not as fun as quickness and as old Brit examples reveals. Suppose your Cdo could go as fast as you'd want, how fast would that be. In Peel's case will require 'against the grain' wheel size for higher tire speed rating.
 
The story was Munro just sawed the knobs off dirt track tyres and rasped them smooth , no flex - no stess . Easy if you know how . :oops:
 
Alrighty Matt that's useful little Burt gem, shaved dirt track not road tires. I recently found out stone cold dirt track tires are softer than heated non DOT road race tires. Tubeless and shaved should up speed rating a couple letters. Will find out what they run on the salt flats next month. Ken Canaga is going try a 920 on NoX so expects to top 160 if he can tuck low yet cock his neck to see ahead a bit. Someday they'll be arresting us for just claiming we broke posted speed limits.
 
Matt Spencer said:
The story was Munro just sawed the knobs off dirt track tyres and rasped them smooth , no flex - no stess . Easy if you know how . :oops:
Click to expand...
Yes, if I recall Mr. Munro took the tread off to the cord to reduce both weight and centrifugal force.
 
All the tires that fit 19 & 18" rims are only rated to sustain 149 mph. Burt tires were also age cracked so he shoe polished over for inspection i read. I have no worry on old hard tires on a normal cycle or Commando but for the rougher ride and not taking traction chances going way over sane speed for conditions, especially wet which THE Gravel travel helped save me on a few surprise slip ups slowing for wet sharp turns letting out clutch in lower gear induced a flat track type skew to get back in line in time. On my Suvee about 100 mph becomes straining on it and me but on Peel 120 was comfy limit till needed to tuck down to go faster more quickly. Its nerve wracking to hang on till top out.
 
hobot said:
All the tires that fit 19 & 18" rims are only rated to sustain 149 mph.
Click to expand...

Not quite true, Steve.

There are ZR and W rated tires available in both 18" and 19" sizes. Z-rated tires are rated at "above 149 mph." No specific upper speed limit given. And they are available in 18" sizes. I'm running Z-rated Bridgestone Battlax BT-020 radials in 120/70ZR18 and 110/80ZR18 on my Norton for Bonneville. SCTA allows use of ZR tires for speeds up to 199 mph. Bridgestone now sells the same sizes in their T30 tires, with a W speed rating, which has an upper limit of 168 mph. They also offer it in a W rated 110/80ZR19, as well as a 120/70ZR19 Z rated Exedra Max. I haven't looked at other brands lately, but I think there are probably other brand ZR tires available in 18" and 19" sizes.

Ken
 
Matt Spencer said:
The story was Munro just sawed the knobs off dirt track tyres and rasped them smooth , no flex - no stess . Easy if you know how . :oops:
Click to expand...

They also tried to knock Mr Munro back on safety grounds at Bonneville. In Australia the coroner sometimes gets involved.
 
Thanks for good news list Ken as couldn't find over H rated on my own prior. Hope yours expands nicely this year.
 
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