MC21 SP Rothmans Special

Build Date:	October 2009
Builder:	Tyga Performance
Motorcycle Model:	TYGA MC21 SP Rothmans Special
Products Used:	MC28 bodywork and tank, GP chambers with carbon Kevlar silencers, VHM heads with hi flo reeds, PGM III conversion with jetting, CNC triples with adjustable fork caps, upgraded brakes with braided lines, TYGA step kit, lightweight sprocket holder and wheel spacer kits, key carbon parts and lightweight stays. All TYGA products used listed below.

This particular bike started off as a tired auction MC21 and desperately needed some loving attention to bring it back to full working order. We decided to strip the bike down and rebuild it into a daily ride, which would at a glance look completely stock but is actually packed with a lot of our latest TYGA parts as well as some old popular favourites too.

You will notice that the bodywork is actually MC28. We preferred the 28 shape to get the authentic Doohan NSR500 look. This was ordered brand new along with the fuel tank and is supplied from Honda all nicely stickered up so it saved us the usual dramas at the paint shop.

The panels almost drop straight on the MC21.

MC21

MC28

The main issues are that you need two stays for the front seat cowling positions from the subframe and we choose an MC28 subframe to move the fold down pegs further back to clear the seat cowling. The MC21 instrument just touches the screen so we put a foam pad on the top to protect it. Other than that, it is plain sailing and the Rothman’s scheme gives the bike a very clean and fresh appearance.

Engine is rebuilt with new crankshaft, top end and clutch parts and runs stock porting. Performance enhancements were moderate with the bike treated to a set of GP stainless chambers with carbon/Kevlar silencers, VHM heads, carbon reeds fitted on hi-flo reed valves as per our power up kit. The 21 loom is spliced and runs a PGM III and the airbox lid modified and the carbs jetted to suit. The bike now puts out a healthy 62 horsepower at the rear wheel and pulls cleanly from around 2500 rpm. There is even enough grunt to carry a passenger through the traffic, though a passenger of course does upset the sweet handling of the NSR.

Suspension has been worked on at both ends. At the front, the bike has TYGA full adjustment caps for enhanced setting and the forks themselves are held in TYGA CNC machined triple clamps. The rear shock is an MC21 SP unit which has been stripped and refilled with nitrogen. The remote reservoir has been modified by TYGA and has a special end piece fitted with a valve for easy refills. Stock springing is used throughout taking into consideration that this is a street bike first and foremost.

Braking is fairly conservative and in keeping with the stock credentials of the bike. The MC21 lowers on the forks have been replaced with MC28 ones so the SP2 calipers can be mounted directly. These bite on MC22 rotors which are the same size as stock and look prettier than the MC21 originals. The rear brake is rebuilt but otherwise stock. Stainless brake lines are fitted throughout.

The bike was put on a diet. The front meter stay and upper mirror stay have been replaced with TYGA aluminium ones. The rear sprocket holder is TYGA which saves a great deal over the stock one, as does an AFAM rear sprocket and of course the Magtek wheels have our lightweight wheel spacer kits fitted and were repainted white and fitted with Pirelli Dragon Corsa rubber. The clutch cover is carbon and together with the exhausts and triple clamps, there has been a considerable weight saving over stock. Other carbon parts include a TYGA rear hugger, radiator shrouds, meter and filler covers and heel guards.

The bike is fitted with a host of other CNC parts such as the TYGA step kit which has solved the once sloppy gear change and significantly improved ground clearance. We also fitted CNC brake and clutch levers and lid for the front master cylinder top up tank. While we were shopping for new Honda parts, we also bought new top up tanks to replace the discoloured and stained top up tanks for the radiator, the auto lube and the front master cylinder. We also installed a new screen and all the body fasteners. Cables and bearings were replaced as a matter of course and most of the bolts and stays which were not replaced, were re-zinced or would look out of place on this very new looking 20 year old bike.

So how does it ride? It just feels like a very taught and lively MC21 should do. The power builds up gradually and then the revs surge forward in good old two stroke fashion. It quite difficult to ride sensibly knowing there is that top end waiting for you to open the throttle but riding around at town speeds is a breeze. The dry clutch gets lot of attention at the lights from the locals on scooters who I am sure think the bike is about to go pop. Any thoughts of that are soon dismissed as soon as the lights turn green. The beauty of a bike like this is in most situations, it is king of the pile. It has performance advantages over almost anything in an urban environment and can turn much quicker than bigger bikes. It took a while for the brakes to bed in but now they have, the bike pulls up sharply with one finger. A track or twisty road test is next to push the tyres and suspension to the limit. I can’t wait!

Below are some pictures of this bike with some prototype titanium coated stainless chambers fitted with our new carbon/blue silencers. Like them or not? Please let us know your opinions.