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Sensei
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Cool looking bike, and NOT to detract from his efforts, but that took a LOT of work (and NOT normally aspirated) to pick-up only 14 MPH at the top end...(good running stockers will do 93)... Is it stock displacement?...Carbed or injected?....Any links to his build?...More pix?....
I would think you could come close without the blower,(at least crack 100) just by "adjusting the breathing", changing the final gearing, and eliminating any excess weight
 

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i think i'm fat, because my little 350 wouldn't do 93 even down hill with a tail wind.
 

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Sensei
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Jason.... Bonnie has Five miles to achieve top end..... I bet if you held yours wide open for five miles you would be surprised.... You'd probably have a legal document to prove your speed too (Ticket)... :lol:
 

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Sensei
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Yeah GB...I Love it, but can't figure out why its top end was 107 instead of in the 120 range.... :D
 

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66Sprint said:
Jason.... Bonnie has Five miles to achieve top end..... I bet if you held yours wide open for five miles you would be surprised.... You'd probably have a legal document to prove your speed too (Ticket)... :lol:

i have a stretch of road by my house that is about 7 miles flat, no cross roads, and i could only muster about 82 out of mine..

that was based on the speedo though and not GPS or anything more accurate.

Probably could have been carb related though, as i never really tried to tune it for top end.
 

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Sensei
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Jason, It's not necessarily the carbs.....could just be the quality of the fuel (Octane rating)....
Also, Most non-profession mechanics don't realize that something as usually unconsidered as a worn or mis-adjusted drive chain/sprockets can reduce performance by as much as a 10% factor.... Something like that alone could theoretically render a 90 MPH capable bike to having a top end in the 81 MPH range.....Another 4 to 6% increase/decrease can be alotted to having (or not) correct TIRE pressures......There are LOTS of other small adjustments that affect performance.......
It is usually the cumulative effects of many factors that will determine overall performance.....
 

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Discussion Starter · #9 ·
I replied to his post to see if there were more details on the bike and I'll report back when I hear something.

Yea...I've always heard these 350s could haul even with their stock setup. Still not quite confident enough to push mine too fast (or have the proper attire) so that will have to wait. And I'm sure every little adjustment counts when you are approaching these speeds.

Was wondering if anyone knew what that black, square object forward of the rear tire was. With the two vertical white stripes going down it. At first I thought battery but I would think they would run with a capacitor eliminator. Maybe a stack of weights to keep the rear down? Sorry, I don't really know much about these bikes that are modified for speed. But can certainly appreciate all the effort!
 

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66Sprint said:
Cool looking bike, and NOT to detract from his efforts, but that took a LOT of work (and NOT normally aspirated) to pick-up only 14 MPH at the top end...(good running stockers will do 93)... Is it stock displacement?...Carbed or injected?....Any links to his build?...More pix?....
I would think you could come close without the blower,(at least crack 100) just by "adjusting the breathing", changing the final gearing, and eliminating any excess weight

Beware of Honda's notoriously optimistic speedometers. . .
 

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Sensei
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I was... the speedo read at/over 100...The radar gun said 93.....
 

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Sensei
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Since Hondas are notoriously bad at running without a battery, I'd also say it's a large battery for a total-loss supply.... Or at least an "electrics box" to house all his components..... We'll just have to wait for more details..... ;)
 

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OK I will weigh in, I had a new out of the box CB360 back in '75. The 360 has 35 more cc and an extra gear. The best I could ever get out of it on a long flat streach was in the low 80 MPH range. This was confirmed by the Washington SP.
There is no two ways about this, this is a huge achievement and very well done.
 

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I tried to find the trap speeds from the Lightweight production class at the AHRMA event at Daytona. I could swear I saw low 90MPH figures. The production class is exactly that. Although cheating in that class is quite common, it's generally limited to exhaust and other minor things (like a non legal seat).
I do remember in Northern Michigan, on my 305 Super Hawk, my mom (she was a character!) pacing me in her Ford F100 pick up because I was sure my bike would do 120. Well, she said, just under 100. Assuming the F100 speedo was optimistic (which it was-- most are, even now), I'm sure I busted 90MPH.
To hit 107 on the salt IS an achievement! When you talk about going "blah blah" MPH, that's on pavement! Try it on sand (or salt) a whole different ball game!
 

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Sensei
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I'm not doubting his speed, or denegrating his bike.... I just stated that I thought that speed could be reached on a carefully prepared normally aspirated machine, and one would think a blower would have had a greater effect (higher top speed).....

"Doing the ton" (100MPH) was possible on a modified 350 running a "big-bore" kit ( readily available up to 435cc in the day) and a radical cam with only carburation, No blower....Admittedly, on pavement,...not salt....

A properly tuned STOCK CB 175 will "get" to 82 (radar measurement), and the single carb CD 175 (sloper, 4-speed "touring bike" ) was supposedly capable of 130 KPH (80.7 MPH)...
I get 70 MPH (speedo, probably more like 62/63 actual) out of my 175 "mini" running a 12" rear wheel, which mathmatically translates to 90+ if I had full size wheels.....Of course, it weighs WAY less than what a stocker does....and the engine/carbs are not stock...And math doesn't match reality.... Lighten-up guys.... :D :D :lol: :D
 

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"Optomistic" speedometers? :eek:

Does this mean that possibly that little Super 90 I had in high school wasn't really doing 80+?

I'm just mortified. :oops:
 

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My 450, which is totally stock, will bust 100. Actually it'll do about 110 according to my sons GPS. The only mod is one tooth lower front sprocket. Honda's, even now, are horribly overgeared.
Have any of you ever seen redline in top gear on a stock gear ratioed 350 or 450 (or 750 for that matter). I ran my 1971 CB750 for miles in 5TH and about 7800--8000RPM was all it would pull. The speedo said 120-125. My friends 1969 sand cast, with 3 teeth more on the back and one lower in the front would red line in top gear and walk away from me . I always thought he had done some major engine work. He always denied it and, smilingly tell me it's because he was a better rider. Then, he finally gave me his secret. I just dropped one tooth front because I was too cheap to buy a new chain and sprockets. He still pulled me top end but, I was able to get to within a couple hundred RPM of redline and the speedo would show 130!
 
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