358 Vintage Road Racer,page 9

Trish checks out the ergonomics. The bike was fired up for the first time on a Thursday evening in May '09. It sounded good, so we loaded it up in the van and headed for Seattle track the very next day with nervous anticipation. The bike never made it onto the track. Riding around the parking lot was difficult with so many false neutrals, and then the crankcase breather puked out a bunch of oil. We headed home. The engine was torn down for the first time, a crankcase baffle installed, complete with a frothing tower as part of the system...

The Triumph clutch actuating mechanism wasn't a good match for the Jawa clutch, so I found it impossible to get a good adjustment with good cable feel. The solution seemed to be a hydraulic clutch. Here the Triumph tranny end cover gets modified in the mill. The machined piece on the left bottom will be welded on >

The cover has been welded and transitions smoothed out. The welding has caused the case to warp, and the red felt pen marks show where it needs to be straightened after heating with oxy-acetylene. The C-clamps will apply the pressure for it to bend controllably >

Hydraulic clutch cover is finished. Plus, it works very well with good feel at the lever >

May '09 we had 358 on the Cypress dyno, Tuesday and Thursday evenings. I took a selection of main jets from 320 up to 390. It's one of those dynos where it holds the engine under load at intervals up to redline, while the sensors record CO readings. 390 was WAY lean, so we went back Thursday armed with a selection of number drills, plus 450 and 500 main jets. The 500 was getting there, so I drilled it out to .081", which is about a 550 main jet! The CO was now at 6, but the mid range was still too rich. The engine was run up to 5000 rpm quite a few times, and 6000 rpm a couple of times. Cylinder temperatures only reached 140 degrees F, while the rear tire got up to 167 degrees F on the 6000 rpm runs. Best rear wheel HP was 49 with 52 ft/lbs of torque..

We loaded the bike into the van and headed to the Seattle races. There was no time to get fatter needles to cure the mid-range richness. First practice showed the Triumph transmission still wasn't great -- too many false neutrals, especially down shifting into a corner. The richness wouldn't allow the engine to pull cleanly; there just wasn't any snap. The handling and brakes were very nice, however. On the second practice I was heading downhill into turn 3, got a neutral, got it back into second gear, and felt the engine slow, so I pulled in the clutch and called it a day...


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