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I gave James at JHS Racing a bell and booked the bike in for the day. The plan was to start with getting the fueling okay with the FZR600 downpipes and can and then try my two other cans. Then play with the ignition timing. Then maybe try my FZR400 downpipes (if necessary). I asked fellow NG'er Will Pugh if he fancied coming along as it would be a lot to do in a day but could be interesting. So we got to JHS and James got the bike on the dyno. First warm up run showed 60+bhp, second 64bhp, third 66bhp and James just kept on going.

Once the bike was warm James ran a few runs and we looked through the dyno sheets:
Power - 69.7bhp peak and no major bumps or troughs on the way
Fuel ratio - a lovely wavey line, all good there
Gear runs - good power all the way
Torque - 29.4 peak and equal or better to what I had

The motor sounded great as well. James reckoned we could play around all day but to be honest what we had was pretty good and was it really worth the time and expense for marginal gains? Me and Will thought no so that was that. The only other advice James had was that the response from an on-off-on throttle could be better, but that would require changing the cam timing. The cam chain sprockets aren't solid, so I didn't get them 'slotted' when the head was tuned. However, James reckons some time with a file and a fat woodruff key could sort it, so I might look into that later in the season.

The first picture below is what I had from the middle of last season (rrsp motor). The other dyno sheets are based on that and the current set up (rr motor, rrsp head). Big thanks to James again. Hes a good bloke so if you need any dyno work doing give him a bell. Big thanks to Will too. As we had time, we went back to mine and I let Will fit some alternator related bearings into my Triumph. I'm nice like that...

Note - The dyno visit was on Friday. Today (the following Tuesday) I went to Tim Blackmores in Bristol as a friend wanted to see what my bike would read on Tims dyno. Tim didn't get the bike as warm as James had and James said that the bike liked it better when it was hot, so it read a little lower. How much was down to engine temperature and how much down to dyno differences I don't know, but the results are fairly similar (see the last two pics for Tims runs). I've since been told that the engine shouldn't be pushed until the temp gauge is reading 50 degrees plus and that max power would likely be around 80 degrees.

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