Tony Haywood's NRS Replica

[Richard Negus]

I'm not biased of course, but neither am I surprised that Tony's NRS Replica won the competition (MCN today)Some may have seen it at the last NML Open Day or running for the first time at NOC Donington.Wait for the next one though !

[Interpol2471]

What competition? I never read the MCN as normally full of P##P

[John]

"Britains got biking talent" competition. Very impressive bike.Seems Norton is pretty popular at the moment with the public.It's a Spondon framed example, would love to see one with a replica Harris frame, I wonder if Harris would agree to build an exact replica frame just as Spondon did?

[Richard Negus]

[quote="John, I wonder if Harris would agree to build an exact replica frame just as Spondon did?[/quote]They wouldn't for me a few years ago - claimed not to have the press tools and jigs any more.I'm sure a replica could be made if a sample was made available (Hello Ashley, how's Oz ? Still got that frame and rear fork ?)Tony's bike is actually a replica of something that didn't exist ; a Spondon-framed F1 engine. His original plan was for an RCW588 replica but although NML have the pattern equipment for the heavy-duty gearbox casting, all of the gear and shaft drawings seem to have 'migrated' ; perhaps in someones archive ? Building an RCW588 with a standard Commander gearbox would have been a formula for disaster.Tony's F1 engine has an interesting history ; a factory prepared race engine built specifically for a racing car that won two RAC Hillclimb Championships in the early 90's, running on methanol/nitro mix.R.

[Wayne]

Hi richarda very nice bike but have mcn got it wrong again, 170bhp works motor, i thought the castings of this period were light wieght and the rotors made from solid billit, and other special one off,s,I was and still am interested in building somthing similare bike but on the road version, so if you know of another race engine ect please let me know.

[Richard Negus]

Hi richarda very nice bike but have mcn got it wrong again, 170bhp works motor, i thought the castings of this period were light wieght and the rotors made from solid billit, and other special one off,s,.

I don't recall hearing of any power claims for Tony's bike, and 170 seems a bit on the optimistic side anyway for a carburetted motor.RCW gearboxes were definitely of the heavyweight variety ; sand-cast casings, big diameter shafts and even bigger gears ; all to make it survive the engine torque.NRS engines had the immediate advantage of bigger shafts and gears, courtesy of Yamaha ; all castings were standard production but additional machining in some areas took out excess weight. Rotors were standard iron castings with a smaller chamber to increase compression. The significant weight reduction was belt primary drive and a Kawasaki-based slipper dry clutch.To the best of my knowledge, no one has made one-piece rotors for the Norton engine that actually work. The AIXRO kart engine, and its military derivative, still has a two-piece rotor even though the outer is machined from a lump of steel rather than an iron casting. R.

[John]

Richard, could a full NRS 1991/92 race Specification engine (exact in every way) be created by starting with a standard F1 road bike engine and then modifying it's internals? Would be interesting to know if it can be done or if it's not feasible. Thanks/John.

[Richard Negus]

Hi John,Of course it can be done - that was the basis of the race regulations.Most of the mods are metal off the standard production parts, except for the rotors, which need smaller combustion chambers to get the nominal 10:1 compression ratio. Standard rotors are nominal 9:1.Rotor housings need to have the ports enlarged = metal out.Spark plug seating deepened to put the spark closer to the trochoid surafce = metal offEnd and centre plates lightened = metal off.Eccentric shaft standard.Bearings - standardStationary gears - standardFlywheel lightenedGear case lightened = metal off.Yamaha gear set complete (OW01 race kit)Belt primary drive / slipper clutch (combination of special & Kawasaki parts)Water pump - standard Primary cover - cut away to mount water pump and oil pump only.Ignition - take your pick.Flat-slide Keihins.Curly-wurly exhaust.Everything is possible, even the primary drive and high compression rotors if you know who to ask !R.

[Wayne]

Hi RichardSo back to my quetion, are there any rcw/nsr spair parts left for sale that you know of, rotors, farings, tanks, exahusts ectRegards Wayne

[Richard Negus]

, are there any rcw/nsr spair parts left for sale that you know of, rotors, farings, tanks, exahusts ect

Hi Wayne,Sorry to say, Wayne, but I don't know of any such parts. I'm quite sure there are parts out there being 'saved for posterity' and some of the likely candidates, but no more.As I said previously, moulds exist for some of the grp parts, and Spondon would, I presume, be keen to make a replica frame and tank.R.