The Endurance race bike engine had a winter refresh and needed a quick dyno. This prompted me to do some testing but before testing I had a long road ahead of me.

One thing I wanted to test was a bigger reed block but couldn’t find what I needed so thought – make one!

Armed with a big chunk of aluminium I set about cutting and machining it to the size I wanted. Out of all the things Ive made over the years I’ve never made a reed block! And was pleased how it turned out but that was a day and half out of my life – but it had to be done ready for the new MB Reed cylinders I’ve been developing.

Last years testing with the new pipes showed the MBgm Clubman worked well for the endurance race but the new prototype Clubman showed what could be gained and gained where they wanted the power. It was the same with our new expansion chamber, it lifted power where they needed it.

So they wanted me to do them a one off prototype of the Clubman. This wasn’t as straight forward as it seems. The only complaint was – they were grinding the box and U bend on corners and wanted a Clubman that wouldn’t grind down. So I set about redesigning my prototype Clubman thats has been working on every engine we’ve tested. This time with a new exhaust I set about removing and replacing the side that bottom outs – giving near 20mm extra lean. At the same time I made a new U bend.

Now take a straight edge from the tyre to the running boards and you will be grinding the running boards and not the exhaust – but that was 3 days out of my life! But it had to be done to get the new box pipe into production.

It worked and found more power just where we wanted it from 3000rpm to 8000rpm without loosing any power! And as the endurance bike is a road bike this is what Ive been working on for production!

With a carb change we found even more power on the top end with no loss of bottom end.

As the team all came down to do the spannering and learning we had another cracking day!

Mark Broadhurst, ask

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