Tuesday 12 May 2015

A late update

The review of the springspeed nationals is a bit late coming but here it goes anyway....
 Going into this event we still hadn't made it down the track this year, so there was still a few new bits on the bike to test, mostly the new experimental nitrous system with dual fuel solenoids and extra massive nitrous solenoid. 
Picture courtesy of Callum Pudge

The first run then and the huge nitrous solenoid sucked all the electricity out of the battery and it hardly made it down the track, backfiring and spluttering most of the way. This wasn't helped by the fact that the battery charger had been playing up and maybe hadn't charged it fully or at all.
On the next run it didn't do any of those things, it 'calmly' went down the track without incident. Dead slow though. turns out the new solenoid had blown the fuse in the nitrous system so it didn't come on, and it blew the next few fuses i tried too until it finally stopped with a 30amp. Greedy.
The data logger was key to diagnosing this problem, without it we could have been guessing and changing everything for months and at great expense. But the graph shows battery voltage dropping with each solenoid pulse, turning the ignition and O2 sensor off at the same time. 

With no easy way to resolve this issue, i changed back to the little baby solenoid and managed a 7.8 on the next run - but that was with our usual shakey issue of tyre shake and bouncing for the first 200ft or so. On the next run the bouncing was so bad it turned the nitrous activation switch off less than a second into the run, so that was that run over as well. 
The 7.8 was good enough to put us 4th and I'd be up against fellow comp bike deserter Allan Davies, i decided to make a few totally random changes hoping to reduce the launch issues and maybe get through that first round, but it completely didn't work, buckarooing around so bad i wasn't actually in the seat at one point. Crazy thing.
Needless to say, we didn't get through that round. 


The good news is that the rest of the changes to the nitrous system seemed to have worked pretty well, reducing the lean spike that we always had, to the point where it's hardly visible on the logger graph. And the huge solenoid is now for sale on eBay, it's 33amp draw is just too much for a total loss 12.8v system. I'll be looking to buy the next size down, which draws a mere 13amp. 
If we can find a softer clutch setup that works i'm hoping it'll run really well at the next round in june, we have more power in it and it could be it's last chance to go faster if we are to run the new bike at the following round. 

New bike is still coming along steadily. I now have some MTC pistons for it, and valves are now with Roger Upperton - being modified to fit the head. I'm currently making a set of wheelie bars for it, and as soon as they are done and the lathe is free I'm going to make some titanium valve retainers as it's nearly impossible to find any that will fit 6mm valves. Loads of other stuff piling up too, wiring stuff is sat there, cans of paint sat there, steering damper partly done, fuel tap splitters partly done, coil mounts to make etc etc. Plus i need to service the race bike, check it thoroughly for broken stuff and decide on a setup for the next round. Busy busy. 




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