Am following george’s request, but since it’s not a sohc4, doing a separate thread
And sorry for tricking you in with a catchy title, it’s a sohc single with five valves, not 5 cylinders ....
So building this frankenstein kept me occupied on and off for the last two-three years. Frankestein as in: 1992 TZ250 4DP frame, 1992 XTZ660 motor bored to 700cc pretty hotly tuned (12.5:1 CR, twin 38mm flatslides, massive porting, etc.) , ducati 916 fork, TZ250 front wheel, ducati monster rear wheel, one-off isle of man TZ long type fuel tank, Aprilia RS125/250 bodywork, Honda TSR250 “bumble bee” tail, ZX6R carbon silencer, unknown source water radiator and the list goes on. Any wonder why it took a while to match together and complete?
Let’s add to the list various trial and errors iterations for oil tank & venting systems (got precious advice from hipo sohcers on here...), one failed try to build a crank end starter which led to having to build a proper 7HP rear wheel starter, that 700 lump with high CR laughed at any other start method.
But now that it’s up and running as it should, it already repaid the effort with huge satisfaction, and with time in my hands I could even make it pretty, unheard off! First race in Vallelunga everybody was going on with “che bella!” and even Russell Benny, owner of world champion Phase One endurance team gave me his compliments. The guy made my day.
I kind of imagined that riding a pukka race bike would feel different than anything street based and it really is, with 280 lbs weight, 75hp, modern geometry, suspension and tires.... talk about a scalpel, bike limits are way beyond my own. And thats before even running slicks. Will take little steps here, moving on from medium compound contis to softs and then maybe slicks next year. Also still need to get used to use the torque rather than the revs of an I-4.
Only bummer is that for now we are only 4-5 supermonos so no separate category, we’re all grouped to doing regularity with the early 90’s superbikes and 600 supersports. Hopefully more supermonos will pop up and we’ll be racing for real. The category was extremely popular in europe but essentially died when 600’s got so good and cheap to run. Honestly, I am having so much fun diving under those heavy superbikes in turns that i really dont mind.
Last, a personal story. People will tell you that racing bikes are dangerous and that it will all end in tears. Well, for me this one is just the opposite. Two and a half years ago I was diagnosed with Type 1 diabetes and became insulin dependent from day one, that’s pretty much a turned-upside-down-for-life condition. Wasn’t even sure I will even be allowed to race again. So this project kept me going through a really difficult period, giving me tons of motivation and the day I passed my medical test for my racing license renewal I felt like born again. So next time people tell you about the dangers of racing, you have a good story to defend our cause
