Hey all, Iv'e been around the 250 & LSR forums a bit, and just in case this would interest you, Iv'e managed to get a supercharger fitted to my MC19 CBR250R based land speed race bike.
Thanks Grasshopper, the supercharger is an Aisin AMR300 originally fitted to a Subaru Vivito 660cc delivery van, only sold in Japan apparently
Welcome. I have used those little two lobe chargers on everything from Subaru to Morris Minors and so long as you don't spin them faster than about 13,000 rpm they work fine. What sort of frame mods did you do for the high speed on the salt? Like the little fuel tank on the front.
The engine is spun up to 16,000, the blower is undergeared 25% (usually) although its more like 30% now to drop the boost back to 8 lb (It was set up in the 1st instance with stock cams with quite a lot of overlap, after melting a piston during my 1st LSR attempt, I took the opportunity to fit Honda Jade cams, with zero overlap, and lowered the CR to 10/1, this bumped the boost to 15 lb (with zero cam lobe overlap) I have a set of pulleys to go back to 15 lb after I have a successful run. The frame is from a 1980 VT 250, raked to 37 degrees, running the Honda CBR forks. swing arm & wheels That Honda 50 tank up front is just a test tank, sacrificial lamb type in case I get slack purging the methanol after a run. The fuel tank is the seat rear, with the original VT tank being gutted to accommodate the blower & a Harley size battery to avoid voltage drop while starting Tiny
Man this definitely interests us! Welcome to the forum! What sort of speed have you got out of it so far?
Not allowing for wheelspin, taking into consideration the tach error, 116 mph in 5th gear is the quickest it has gone. The pic taken at the 1 mile marker, DLRA Speedweek 2013 a few seconds before I holed #4 piston Tiny
Welcome mate, I have seen your videos on YouTube. Almost jazzed my pants when I head that beast roar into life. Lol
Hey Tiny, Sorry to hear you're selling your bike, maybe one of the forum members will buy it. Is the setup too complex? It's turbocharged and supercharged isn't it? Or am I thinking of a postie bike I've seen run at the salt? I know you've been working on it for years. Would you do anything different if you had your time over? Frankster
Yeah Frankster, it's supercharged (#2), Iv'e run 2 Posties, the 1st was a stroker, 144cc, managed 71 mph #2 was "almost" a postie (well, it had a postie steering head / forks & kick starter, but had a modd'd CB125 "laydown" bottom, with #4 cyl from a cbr600/4 stuck on it, it went 87 mph, then I stripped it to fill the innards with a collection of Carrillo & new oem ****, it never started again (refer,,interest loss) 6 years is about one year past my attention / enthusiasm span. The tuning was the complex part, but that's spot on now (EGT sat on 840 degrees F, coolant temp was 80 C & remained there for 3 miles.) My body is beginning to reject it's miss spent youth (crook back), a mate, Wilso was rider #2 this year, I rode it 1st run, megga clutch slip once I got angry in 5th, so soft cocked it into 6th & rode around the clutch problem (101 mph) Wilso is much more aerodynamic than me, he followed team instructions and left it in 5th, managed 107 mph before the clutch spat it again. I gained sponsorship from Barnett clutches & cables USA in the form of an ultra thin solids, & Kevlar friction disks, with 2 sets of megga springs, there are now 2 extra friction plates resulting in 20% more surface area, I used the 70 lb springs,, I still recon it has a good 125 mph in it, and providing it doesn't hit the "brick wall" of air resistance, it's geared for just over 130 mph $5,500 would get you "Laslo" and a complete MC19 "spare" bike (and a landspeed record if you beat Wilso) I also have a brand new OEM set of valves for sale, or nearly 2 sets of refurbished used valves for sale. Tiny
The humble GoPro does not do the sound justice Ben, if the throttle is given a good blip, my ears get a stabbing pain in them if I'm standing alongside, without a helmet It's a shame it won't be returning to the salt again to show what it is really capable of though, unless it gets a new owner , my 64 y/o body is telling me Iv'e abused it for too long,,,,,