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Discussion Starter · #1 ·
My friend and I would like to build a Cl175-based motorcycle streamliner to run at Bonneville. There's an open record in the 175 class. We're shooting for about 130-40mph(possible?).
What are some good ways to get high rpm power out of one of these? I was thinking stock bore with high-dome pistons (doesn't JB make some of these, in a stock bore?), porting (probably not too hard when all you need is high rpm power), bigger carbs (suggestions?), and a cam if anybody makes one.
The chassis will be basically a very low dragbike type, with stock wheels with alloy rims, and the tank under the seat. Any other suggestions? Thanks, Jimmy
 

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Discussion Starter · #4 ·
My plan is to make a full streamlined fairing, shaped somewhat like a cigar. I'm going to use cardboard bucks and aluminum sheeting(fine mesh) for the mold and then fiberglass mat.
I was planning on laying the steering neck way down to rake out the stock forks and get the bike as low as possible. I'm just not sure if the stock forks would be acceptable (strength-wise). I know the suspension wouldn't work very well, and the steering would be very slow, but I don't think it would need much suspension, and slow steering is a plus for a lsr.
There is a record for 175cc partial streamlined (which I assume is like a dustbin) and it was set with an rs 175 at 133mph. There is a minimum speed for open records, but I'm not sure what it is in this case.
From what I've read about streamlined bikes, I'm hoping 30-40HP will get the bike to around 130mph. I'm also hoping that much power is possible with a cl175 motor when I don't have to worry about low-end or part-throttle. Heck, if the thing did over 100mph with my 210lbs on it I'd be happy. I've had it going 70mph stock, so I'm guessing that's possible with a real swoopy fairing. Jimmy
 

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Discussion Starter · #5 ·
I checked some old posts and JB said something about a megacycle cam for the 175 that sucked because it had too high of a powerband for track use. He also said he had one he would like to get rid of. Maybe that would work?
Anyone know of a good motorcycle streamliner site? The only ones I seem to find are about all-out efforts with two engines positioned behind a sit-down driver, nothing like what I'm planning (basically a lay-down head forward dragbike design). I need to know if I need the outrigger wheels to pop up or if they can just stick out, and how I start the streamliner(push vehicle or just some friends?). Jimmy
 

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Discussion Starter · #7 ·
Yeah I looked at an old post and saw JB said he had something like 23HP at the wheel. So 40 might be stretching it but 30 at the crank sounds achievable, since I won't have class limitations and I'm just going for all-out high rpm power.
With a dustbin I think I'd be in a partial streamlined class, because a dustbin doesn't fully enclose the motorcycle, right? I'm talking about a Burt Munro type streamliner (that's the only one of the type I'm thinking of that I've seen). Jimmy
 

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Discussion Starter · #10 ·
What do you think the biggest expense would be? I know tires are a lot. I'm a certified welder and a bodyman/painter so the frame fab and bodywork is free (except for materials). I was thinking about a grand in the bike(I've only got $100 in it now with two spare engines), but like I said, this is mostly for fun, but I'd still like to go as fast as possible. By the was, the 250 class msl record is 189mph.
I'll have to send in my $60 for the BNI membership to get next year's rulebook before I can really start making plans. Most of the streamlined motorcycle rules on the scta-bni site sound like they only apply to a sit-in msl. Any ideas anyone has are appreciated. Thanks, Jimmy.
 

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Discussion Starter · #14 ·
Thanks for all the input. I'm assuming for now 175 means 175cc with maybe a few extra ccs to allow for a rebuild-type overbore. For the engine some things I had planned on (besides some you listed) were a good cam chain and some pistons like what you use (JB) except in a near stock bore size. I know I'll need as much compression as possible. I remember when I lived in Utah how much the altitude cut my '68 Prix's power, even after rejetting. Do you think stress-relieved, polished stock rods would handle 13,000rpm? I could also lighten the rockers and machine the nuts to half thickness.
For the fairing shape, I made a rough sketch a few days ago. It does resemble the Burt Munro special, just without a tail. I don't think my target speed requires that for stability. I checked out the 175 class records and there are NONE for fully streamlined bikes. Only partial streamlined. That's another reason I want to run in that class. I'm not sure if my engine designation would be vintage gas, or modified gas. Either way it wouldn't matter. If I wanted to I could run alcohol and go for modified fuel. Jimmy
 
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