New project
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Fast Eddie
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Very cool.
Please do treat us to a proper build thread on this, it will be the most interesting thread on here by a country mile !
But I have to say… you're a braver man than me Gunga Din !
What are your plans for it ?
Please do treat us to a proper build thread on this, it will be the most interesting thread on here by a country mile !
But I have to say… you're a braver man than me Gunga Din !
What are your plans for it ?
Hi,
The bicycle is perfect, having been rebuilt for sprinting. But the fast motor was retained by the original owner.
I bought it with an unknown quantity aircooled motor.
The frame has been modified to pull the air thru the motor and out an ejector pipe, so no hot gasses going into the carbs.
First off will be to strip and inspect the engine with pair of very safe hands. Then see what horrors await inside.
Hopefully rebuildable without having to buy lots of major parts. We will open up the inlets and port for a pair of 36mm carbs. It will need an ejector exhaust making.
And put the big lumps together. I dont plan to do anything to the cosmetics, (bar the motor!) minimal wiring, and put a plate on it, and use it on the road. I will change the oil temp guage for (or add functionality of a [GPS?] speedo)
Historic tax, no MOT, no ULEZ. Maybe no lights...
@ UK folks. If I put light on it, does a 1984 bike legally need indicators?? I dont usually if given the option...
First is to clean up and remove all of the transmission from the motor.
The bicycle is perfect, having been rebuilt for sprinting. But the fast motor was retained by the original owner.
I bought it with an unknown quantity aircooled motor.
The frame has been modified to pull the air thru the motor and out an ejector pipe, so no hot gasses going into the carbs.
First off will be to strip and inspect the engine with pair of very safe hands. Then see what horrors await inside.
Hopefully rebuildable without having to buy lots of major parts. We will open up the inlets and port for a pair of 36mm carbs. It will need an ejector exhaust making.
And put the big lumps together. I dont plan to do anything to the cosmetics, (bar the motor!) minimal wiring, and put a plate on it, and use it on the road. I will change the oil temp guage for (or add functionality of a [GPS?] speedo)
Historic tax, no MOT, no ULEZ. Maybe no lights...
@ UK folks. If I put light on it, does a 1984 bike legally need indicators?? I dont usually if given the option...
First is to clean up and remove all of the transmission from the motor.
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No, not until August 1986 according to the MoT regulations.
MOT inspection manual: motorcycles - 4. Lamps, reflectors and electrical equipment - Guidance - GOV.UK
Headlamp, position lamps, stop lamps, direction indicators, rear registration plate lamp, rear reflector and direction indicator ‘tell-tale’ rules and inspection for motorcycle MOT tests.
Fast Eddie
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Sounds like a good plan.
Who’s will those ‘safe hands’ belong to?
You’re not tempted to go full on Spray / Nation / Haslam JPS replica then ??
The sound that a ‘sorted’wanna them makes on full chat is unique, and fabulous !
I met Tony Haywood yesterday, and we came up with a plan. He is kindly going to school me on the strip (not without him!), evaluation, and then we decide what needs doing.
I was a bit sad to pass this on in part ex- ...
With the large humped seat, and a black paint job many moons ago, I though the gold letting fittingly confusing...
A great bike, and my interpretation of what a small niche motorcycle factory could turn out in about 2005...
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Far Out .
Of course , youll use the full race exhaust system , and otherwise keep it a sleeper . stock looking . ' Oh No , it's just a standard Norton ' .
Of course , youll use the full race exhaust system , and otherwise keep it a sleeper . stock looking . ' Oh No , it's just a standard Norton ' .
Engine and gearbox have now parted company.
I had to remove the chain/ gaiters/ final drive cover from the unit as received. A great idea, but not for me on this build. Very effective tho as chain and sprockets had no appreciable wear.
Covers off, noting that absolutely everything has been glued together with silicone!
No gaskets, which is a novel on a british bike for me (and even actually on the Yamaha singles which were my other affliction).
Of course you can only go so far before needing some new tools. Lack of a clutch spring compressor stopped play for a couple of days, and of course there are a few other little bits I noticed that were missing, meaning the first of many orders (and many many pounds!) to Andover for the project.
But now I have the gearbox off (which I will look inside, but hope will be ok). No awful noises or graunchy shafts. Its based on a 5 speed Triumph unit, but I am not sure how closely, or if its similar to a triumph clutch. It rather looks like a commando unit, but heavier duty.
![IMG-20250516-WA0005[1].jpeg](https://www.accessnorton.com/attachments/img-20250516-wa0005-1-jpeg.119830/ "IMG-20250516-WA0005[1].jpeg")
If anyone knows of a supplier for a clutch holding tool (or indeed an engine lock tool) for this, I'd appreciate it, but as Andover dont have one its probably unlikely.
Yes, they run quite hot!!! Everything is clean tho, which is a good sign I think?
Ok, gearbox in the shed for a wash down and look over, then I will clean up the rotormotor and think about taking it to see a man who knows what he is talking about. Cheers!
I had to remove the chain/ gaiters/ final drive cover from the unit as received. A great idea, but not for me on this build. Very effective tho as chain and sprockets had no appreciable wear.
Covers off, noting that absolutely everything has been glued together with silicone!
No gaskets, which is a novel on a british bike for me (and even actually on the Yamaha singles which were my other affliction).
Of course you can only go so far before needing some new tools. Lack of a clutch spring compressor stopped play for a couple of days, and of course there are a few other little bits I noticed that were missing, meaning the first of many orders (and many many pounds!) to Andover for the project.
But now I have the gearbox off (which I will look inside, but hope will be ok). No awful noises or graunchy shafts. Its based on a 5 speed Triumph unit, but I am not sure how closely, or if its similar to a triumph clutch. It rather looks like a commando unit, but heavier duty.
If anyone knows of a supplier for a clutch holding tool (or indeed an engine lock tool) for this, I'd appreciate it, but as Andover dont have one its probably unlikely.
Yes, they run quite hot!!! Everything is clean tho, which is a good sign I think?
Ok, gearbox in the shed for a wash down and look over, then I will clean up the rotormotor and think about taking it to see a man who knows what he is talking about. Cheers!
Fast Eddie
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Hope he doesn’t find owt like this…
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A bit of progress. I got into the motor after cleaning everything up. ("Clean" being a relative term).
Relief- The motor is perfectly salvageable, but will need new seals, and the end plates moly'd (and ground).
(Cant seem to add pictures now, which is weird? Has something changed on the site??)
Its an early motor, evidenced by the 1-piece apex seals, and likely a service exchange motor. Its not been built absolutely perfectly... But has done high mileage which is probably a good thing?
Crucially the eccentric shaft was good!! PHEW!! So that saves me buying another bike, to get the motor, to rip it apart, to make a large pile of heavy bits that are quite worthless...!)
I think I will re-use the SU carbs for now, and keep the intake stock (bar the fresh air feed, so not pulling in hot air from the plenum).
First is to get the casting stripped of any other bits, pressure washed, acid dipped to remove the OEM powder coating and then vapour blasted.
Then clean up the rotors (de-coke)
Then get the wallet out.... oooff!
Cheers, any tips or reminders on how I upload photos appreciated!)
Andy
Relief- The motor is perfectly salvageable, but will need new seals, and the end plates moly'd (and ground).
(Cant seem to add pictures now, which is weird? Has something changed on the site??)
Its an early motor, evidenced by the 1-piece apex seals, and likely a service exchange motor. Its not been built absolutely perfectly... But has done high mileage which is probably a good thing?
Crucially the eccentric shaft was good!! PHEW!! So that saves me buying another bike, to get the motor, to rip it apart, to make a large pile of heavy bits that are quite worthless...!)
I think I will re-use the SU carbs for now, and keep the intake stock (bar the fresh air feed, so not pulling in hot air from the plenum).
First is to get the casting stripped of any other bits, pressure washed, acid dipped to remove the OEM powder coating and then vapour blasted.
Then clean up the rotors (de-coke)
Then get the wallet out.... oooff!
Cheers, any tips or reminders on how I upload photos appreciated!)
Andy
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Were you a VIP member then?
- Joined
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- Messages
- 21,102
Ok, thanks. Jerry deals with that side of things so hopefully he will be in touch.
Pics:
Left hand end plate. Some blow by from side seals, which were very coked up with carbon. Springs werent great, but ok.
Its a bit scored, but will flatten out ok. Will be getting it Moly'd anyway.
Quite a lot of carbon build up on the rotors. 1 piece apex seals shows possibly an early engine? Rotor bearing is ok (will be replaced) and the eccentric shaft is ok.
The rotors are CR 8.6, which will work for me. They can be anyting from (I think) 7 to 9 and a bit....
Some light scuffing on the rotor chamber, but I am told this is nothing to worry about? I am unsure as I am a total noob if we are looking at the intake or exhaust!
RH side plate is a bit scuffed too, due to (I think) somewhat ill-fitting side seals on the rotor. This should clean up too, but the issue being that it may already be too thin. Clean up, mic'ing and checking reference limits will tell me whats next.
But I was much cheered at lack of major parts to buy. All seals. Mean bearings. Rotor bearings. Rebuild the box. Rebuild the carbs. Get the exhaust made.... 'Ulp!
On the plus side, I now have the V5c in my name, and subsequently registered as Historic for tax, MOT and ULEZ considerations.
More later, cheers!
Andy
Left hand end plate. Some blow by from side seals, which were very coked up with carbon. Springs werent great, but ok.
Its a bit scored, but will flatten out ok. Will be getting it Moly'd anyway.
Quite a lot of carbon build up on the rotors. 1 piece apex seals shows possibly an early engine? Rotor bearing is ok (will be replaced) and the eccentric shaft is ok.
The rotors are CR 8.6, which will work for me. They can be anyting from (I think) 7 to 9 and a bit....
Some light scuffing on the rotor chamber, but I am told this is nothing to worry about? I am unsure as I am a total noob if we are looking at the intake or exhaust!
RH side plate is a bit scuffed too, due to (I think) somewhat ill-fitting side seals on the rotor. This should clean up too, but the issue being that it may already be too thin. Clean up, mic'ing and checking reference limits will tell me whats next.
But I was much cheered at lack of major parts to buy. All seals. Mean bearings. Rotor bearings. Rebuild the box. Rebuild the carbs. Get the exhaust made.... 'Ulp!
On the plus side, I now have the V5c in my name, and subsequently registered as Historic for tax, MOT and ULEZ considerations.
More later, cheers!
Andy
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In progress!
Intermediate plate. Look how grotty that cooling passage is between the 2 chambers! Those are the springs that sit under the side seals which remained on he plate when lifted off.
RH side plate plate, with eccentric shaft. These are NLA, so I was very pleased to find it serviceable!
Right hand side plate showing the integral primary drive casting. You can see where the gearbox bolts up. Interestingly, I havent found any gaskets on this engine. A novelty!! with Brit stuff, and it is definitely very nicely engineered.
Cheers
Andy
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Real life has gotten in the way of this already quite slow project...
Nonetheless I have got the major castings cleaned up (degreaser, toothbrushes and pressure washer), and all of the fittings, studs, dowels and fasteners. Given the crustiness of the outside, I was not surprised that many did not give up without a fight. Some replacements needed...!
This end plate may be an issue... will need to measure and see if there is enough meat left to get these scores out?
Below is the (nice, clean) intermediate plate with carries cooling air through the into the middle of the engine, and then through the centre of the rotors before exiting via the engine mounts...?!
Rotors were a bit of a mess, with 3 surfaces to clean up. Over cleaner did well...
(Cooling) Air passages inside the rotors are vaned:
The casings will be acid dipped to remove the OEM power coating and then vapour blasted.
Time to start making a shopping list too...
Once assembled, it will be a gearbox rebuild, and then onto carbs.
I am itching to get it together!
Thoughts will have to turn to an ignition system soon too...
Cheers, Andy
Nonetheless I have got the major castings cleaned up (degreaser, toothbrushes and pressure washer), and all of the fittings, studs, dowels and fasteners. Given the crustiness of the outside, I was not surprised that many did not give up without a fight. Some replacements needed...!
This end plate may be an issue... will need to measure and see if there is enough meat left to get these scores out?
Below is the (nice, clean) intermediate plate with carries cooling air through the into the middle of the engine, and then through the centre of the rotors before exiting via the engine mounts...?!
Rotors were a bit of a mess, with 3 surfaces to clean up. Over cleaner did well...
(Cooling) Air passages inside the rotors are vaned:
The casings will be acid dipped to remove the OEM power coating and then vapour blasted.
Time to start making a shopping list too...
Once assembled, it will be a gearbox rebuild, and then onto carbs.
I am itching to get it together!
Thoughts will have to turn to an ignition system soon too...
Cheers, Andy
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Andy, that's a very nice project you've got yourself. I presume you are in the "norton rotary enthusiasts " facebook group for all the best advice on norton rotary bikes.
I don't know what power and revs you are ultimately aiming for and while you can almost double the power, the air cooled engine won't last very long and neither will the triumph gearbox. 110 hp with 30mm Amals, standard ports and exhaust ejector should be more than enough and you shouldn't need to exceed 8,000 rpm. The rotor bearings don't like going much over 10,000 rpm. It is still however, air cooled and the water cooled engine would be preferable but obviously you have to use the one you have.
When choosing carb and port sizes remember that, for induction flow rates, each rotor is equivalent to a 200 cc 4 stroke single.
The eccentric shaft may let you down if high revs and seriously high power are desired. If you examine the air passages you will see that they cut well into the fillet radius which is itself rough machined. On the water cooled engines I had the material quality improved, the holes repositioned and the surface finish improved and shot peened (I never checked to see if that all happened and some early Commanders may have missed the change).
The molybdenum mod is sensible although yours and many others didn't need it. I didn't have the time to investigate why some engines wore quickly while others, including all the aircraft and drone engines, were unaffected. I could probably have found a cheaper and easier fix for the problem but time and money (lack of) were against me and the factory.
You could consider an extractor fan instead of the exhaust ejector.
Have many enjoyable hours with it.
I don't know what power and revs you are ultimately aiming for and while you can almost double the power, the air cooled engine won't last very long and neither will the triumph gearbox. 110 hp with 30mm Amals, standard ports and exhaust ejector should be more than enough and you shouldn't need to exceed 8,000 rpm. The rotor bearings don't like going much over 10,000 rpm. It is still however, air cooled and the water cooled engine would be preferable but obviously you have to use the one you have.
When choosing carb and port sizes remember that, for induction flow rates, each rotor is equivalent to a 200 cc 4 stroke single.
The eccentric shaft may let you down if high revs and seriously high power are desired. If you examine the air passages you will see that they cut well into the fillet radius which is itself rough machined. On the water cooled engines I had the material quality improved, the holes repositioned and the surface finish improved and shot peened (I never checked to see if that all happened and some early Commanders may have missed the change).
The molybdenum mod is sensible although yours and many others didn't need it. I didn't have the time to investigate why some engines wore quickly while others, including all the aircraft and drone engines, were unaffected. I could probably have found a cheaper and easier fix for the problem but time and money (lack of) were against me and the factory.
You could consider an extractor fan instead of the exhaust ejector.
Have many enjoyable hours with it.
cliffa
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Hi Andy, that looks like a terrific project! I’m very jealous as I’ve always fancied a rotary.
My brother, (who you may remember you met a few years ago) served with Den, the guy who is Allden’s exhausts. He has some experience of rotary exhausts, so may be worth having a chat with him. Here’s an example of his work…
More pictures here..
drive.google.com
My brother, (who you may remember you met a few years ago) served with Den, the guy who is Allden’s exhausts. He has some experience of rotary exhausts, so may be worth having a chat with him. Here’s an example of his work…
More pictures here..
Alldens exhaust. - Google Drive
drive.google.com
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Hi guys, thanks for the thoughts!!
Hybridracer- I am not going for mega power. I may throttle back on the initial plans, as I see I actually have quite a lot of standard parts for the inlet... 80 hp is probably going to be ok, so perhaps the carbs initially suggested may be folly. I wanted to avoid pulling inlet air through the plenum (frame has been modified), and instead run cold air in. Thus also the extractor exhaust (which I am also a bit nervous of, as to how much cooling this will provide on a roadbike, albeit a silly one).
So rather than build a monster, I would like to build a lightly modded (sensibly modded?!) bike. A few extra horses from the cold air in and better breathing exhaust would not go amiss.
As yes, the gearbox being a weak link, this will get a rebuild as a matter of course.
>>When choosing carb and port sizes remember that, for induction flow rates, each rotor is equivalent to a 200 cc 4 stroke single.
Interesting....
>>The eccentric shaft may let you down if high revs and seriously high power are desired.
Nope, not going nuts...!
>>You could consider an extractor fan instead of the exhaust ejector.
Love to, but thats another development journey... I am going to get a good baseline first I think before major changes.
Whats your handle on the FB group Hybridracer?
Cliffa- yes I will need a pipe. Am not sure yet what will be best, I think I have two options, and that wont be very cheap. Some FB posts advised me against ejector exhaust on a roadbike.... But I like the idea. Even if my neighbours absolutely wont!
Thanks guys, I really appreciate the input. Once I get the cases off for dip/ blast I will be getting the shopping list made up. Mostly bearings (somewhat complex), seals. Will get opinion on re-using the rotor seals and springs...
And I am not touching the gearbox till the engine is buttoned up!
Cheers, input appreciated!
Andy
Hybridracer- I am not going for mega power. I may throttle back on the initial plans, as I see I actually have quite a lot of standard parts for the inlet... 80 hp is probably going to be ok, so perhaps the carbs initially suggested may be folly. I wanted to avoid pulling inlet air through the plenum (frame has been modified), and instead run cold air in. Thus also the extractor exhaust (which I am also a bit nervous of, as to how much cooling this will provide on a roadbike, albeit a silly one).
So rather than build a monster, I would like to build a lightly modded (sensibly modded?!) bike. A few extra horses from the cold air in and better breathing exhaust would not go amiss.
As yes, the gearbox being a weak link, this will get a rebuild as a matter of course.
>>When choosing carb and port sizes remember that, for induction flow rates, each rotor is equivalent to a 200 cc 4 stroke single.
Interesting....
>>The eccentric shaft may let you down if high revs and seriously high power are desired.
Nope, not going nuts...!
>>You could consider an extractor fan instead of the exhaust ejector.
Love to, but thats another development journey... I am going to get a good baseline first I think before major changes.
Whats your handle on the FB group Hybridracer?
Cliffa- yes I will need a pipe. Am not sure yet what will be best, I think I have two options, and that wont be very cheap. Some FB posts advised me against ejector exhaust on a roadbike.... But I like the idea. Even if my neighbours absolutely wont!
Thanks guys, I really appreciate the input. Once I get the cases off for dip/ blast I will be getting the shopping list made up. Mostly bearings (somewhat complex), seals. Will get opinion on re-using the rotor seals and springs...
And I am not touching the gearbox till the engine is buttoned up!
Cheers, input appreciated!
Andy
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