Marks TOURING TORQUEY TUNE Cylinder the 3T’s
As I was bashing ideas around my head designing the Race-Tour cylinder kit I wanted to do a Reed Valved cylinder, but the extra cost meant it would have been so expensive it wouldn’t have sold. I knew producing a good cylinder in the UK was going to be expensive any way. I’ve always been one to do a lot of one off cylinders my Power Valve cylinder is well documented. When I took the plunge to make the RT kits I had been playing around with some other cylinders, originally the first cylinder was going to be a TS1 style copy but with better porting spec.
This cylinder was delivered to the pattern makers who sat on it a few weeks, I was busy any way, the pattern makers wanted me to alter it in some way when I picked it up a few weeks later it just wasn’t right. It’s strange you work on a design everyday for weeks and think, perfect, forget about it, leave it a few days or a week or so and re address it and you seen things you didn’t before. This reed cylinder used a blank Monza and used Boyesen ports from the inlet port into the transfers which I had done in 91, remind you of anything? Yes the RB! I also had sub exhaust ports either side of the exhaust port and above the transfer ports which I had done in 96, remind you of anything? Yes the Super Monza! And this was before the RB or Super Monza had come out.
If I’d pulled my finger out I would have been years ahead of the RB and Super Monza. It was so close, if the pattern makers had pulled their finger out we would have had a high powered kit. When the first RB was delivered to the Koln show I asked Airsal if I could see it, the answer was………. why are you asking, everyone is asking it’s the most asked about cylinder we have ever made, we can not show you until Mr Kemp visits us tomorrow!
That night I went out with the Koln guys and met a German Scooterist who had managed to see the first RB and described it to me! Exactly how I had designed my one off cylinder! Dam I had dragged my heels too long and Ray had beaten me to a new cylinder.
On the way home at the airport there was a que for the plane, at the back was Ray and Ben in suits with a bag. We swap pleasantries but I saw the look in Rays face ‘Of all the bloody people to bump into it’s that gob shite Broadhurst! Minutes later Sticky turned up. I told him Ray had the cylinder in the bag and Sticky did his best to get to see it. I think if I wasn’t there it would have come out, but me and Ray had crossed paths when the Rapido came out. Me and Ray got over our little misunderstanding after I apologised and we’ve been fine ever since. I still have his hand typed letter some where threatening us with court action and demanding we paid our bill. At the time I did the right thing made a phone call and appologised to Ray, Ray even sent me a really nice hand written Christmas Card after our troubles last year and contrary to popular belief I really like Ray and always have.
Anyway Sticky did his best to worm out seeing the new RB and Ray was having non of it. We even suggested that it would make a great photo of Ray and Ben landing in the UK with a photo of them holding the new cylinder on the runway! I even suggested I would be nowhere near so no secrets was let out and still no joy. It was hilarious when we got off the transfer bus and Ray and Ben ran off across the tarmac and was first through pass port control never to be seen again!
I had been doing Reed Cylinders before the TS1 came out, I knew the benefits but fitting a Reed on the left side was difficult. I did toy with doing a Reed Touring cylinder which could have been the RT. But it looked impossible to do and keep the carb in the standard place to use the air filter box. I’d done it using the Kart Reed block off the GT 190 cylinder with my power valved engine but I wasn’t happy with power output because of the reed. In the end I did a piston ported cylinder which we called the Race-Tour cylinder simple and filled a gap where we saw a higher percentage of people who would have bought a kit.
As we did the RT kit there was a demand for a new bolt on Retro Reed Valve, again not an easy job to get close in. I kept looking at the problem and addressed the issues over a 3 month period, researching Reed blocks and rubbers and in the end the only way around it was to machine fins to get the Reed as close to the piston as possible, this was called the MB Shorty Reed Block. As I kept addressing the Reed Block conversions I really wanted to use the Yamaha RD350 power valve or Banchee Reed Block for reasons listed everywhere. I had been using these since 1985 with no problems at all, we could get good supplies and spare Reed Petals any where. But the block is big when you think it’s not.
And it’s here I decided a new cylinder could be made, based on the RT kit which is excellent and under rated but with a Yamaha block added and aimed at a very simple torque monster engine that would suit everyone from a engine using a 18mm carb to a 35mm carb.
Scooter Center put my piston ported RT cylinder into production to see how they sell, we can never predict these things and given time without pressure I would have gone down the road of this one off cylinder as the BGM version. And as time went on the MBgm Kit kits sold in the thousands and became a popular kit!
I designed this cylinder for my own Pushpak which now lives in the shop and was built for the Euro in Spain. In the end I didn’t go as the ignition let me down 3 hours before the ferry was due.
The plan was me and Mouse was going to the Euro together, me on my Pushpak with this cylinder……… 5 speed gearbox………. 9 plate clutch……… the list is too much. As I had finished Mouse’s bike and done a few engines for other people to get to the Euro and done all the tests on the new MBgm Clubman I had left it too late to get mine done on time, even though I started the Reed Cylinder 8 months before! Mouses used one of the first RT kits I knew the bhp of it after a few years of development and testing and had to de-tuned mine to ride with Mouse the long way round through Europe. Even though de-tuned my bike both bikes we set to cruise at 70 all day, trust me we had been out testing on long rides and races for 2 years before the RT hit the road. Mouse’s Green bike was around 21bhp mine was around 25bhp.
I used this cylinder on our motorway challenge and it performed perfectly and with some more miles put on it, when it was stripped the Titanium rings hadn’t worn at all.
So here it is and maybe one day we may produce this reed cylinder! Edit – years later I had perfected with hundreds of hours testing a new RT Reed cylinder and should be in production in 2023!
Mark Broadhurst, any questions email mark@mbscooters.co.uk
