Pierre TEBEC, french racer, rode also a 350 A7R not RA on 1969 in some GPs
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| Author: | husson73 [ Mon Jan 23, 2012 4:32 am ] |
| Post subject: | Re: 1969 A7RA |
Pierre TEBEC, french racer, rode also a 350 A7R not RA on 1969 in some GPs
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| Author: | husson73 [ Mon Jan 23, 2012 4:33 am ] |
| Post subject: | Re: 1969 A7RA |
Pierre TEBEC, french racer, rode also a 350 A7R not RA on 1969 in some GPs BTW would be curious to know if the 350 raced by Offenstadt on 1970 GP was an A7RA 
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| Author: | A7RA [ Mon Jan 23, 2012 5:38 pm ] |
| Post subject: | Re: 1969 A7RA |
I've attempted to find racers who may have raced a Kawasaki in the 1969 FIM 350 gp class and the only one I've found is D. Simmonds. Don't know if he rode an A7R or an A7RA. I do know that there were only 2 A7RA's built (frame part number F-1001 & 1002)for the daytona 200 and that F-1003thru F-1010 were A1RA's. Also F-1001 was sent back to Japan and adapted for the H1 engine and became the prototype for the H1R. I have 2 A7RA engs. (part number 01 and #04), so it makes sense that there were 2 other A7RA eng's made and they could have been installed in a A1RA frame. I don't know what the total part number of RA frames built worlwide was (possibly 13+) of which I only know of 1 that started life as a A7RA. Love to see proof of another and here the total part number of RA's. I would think that Simmonds took back his Daytona A1RA plus another RA frame and 1 or both of the A7RA eng's to race along with his 125 kawa. racer in the GP's. |
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| Author: | Ric [ Mon Jan 23, 2012 9:14 pm ] |
| Post subject: | Re: 1969 A7RA |
Cool.....Why the front fender........fork brace ? |
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| Author: | H2RTuner [ Mon Jan 23, 2012 10:02 pm ] |
| Post subject: | Re: 1969 A7RA |
Actually, the factory found that air being moved off the front tire in normal operation, traveling upwards from the rear of it, was displacing cooling air over the top- of the tire. Leaving the front fender on was the fix, stopped the air thrown up off the rear of the tire from pushing cooling air away from a normal path over the top of the tire, and to the cylinders. This became even more critical when the first H1R's were begin developed, center cylinders ran a good 75 to 80 degrees hotter than the outsides, until the front fenders were re-installed. Fenders on, center cylinders dropped temps to approximately 10 degrees COOLER than the outside cylinders. This also allowed for more equal timing and jetting specs than without the fender in place. |
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| Author: | Leo [ Sun Jan 29, 2012 12:02 pm ] |
| Post subject: | Re: 1969 A7RA |
Never figured the fender would make any difference in cooling, let alone the effect being that significant. Have always used a fender, and never had any trouble with the centre cylinder. How did they measure diff in cyl temp anyway. in an era without laserguns, thermocouples or EGT's? Interesting info. |
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| Author: | Jim [ Sun Jan 29, 2012 12:25 pm ] |
| Post subject: | Re: 1969 A7RA |
Leo wrote: How did they measure diff in cyl temp anyway. in an era without laserguns, thermocouples or EGT's? Interesting info. Thermocouples have been around longer than we have, with analog meters used before digital ones were available. |
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| Author: | Ja-Moo [ Sun Jan 29, 2012 12:47 pm ] |
| Post subject: | Re: 1969 A7RA |
I didn't run a front fender on my race bike for years and never saw more than 20 degrees difference on the center cylinder with a temp gun. Even ran Daytona. From what I have read, AC motors only need an air speed of 20 mph for optimum cooling, as that gives the best contact time for the heat transfer. There are many other factors, but my limited experience didn't show a need. My 2 cents........ 
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