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Discussion Starter #1
I'm giving serious consideration to doing the following:
- having my T100 dyno'd as it is currently configured.
- having it dyno'd again after advancing the exhaust one tooth
- having it dyno'd a third time after also retarding the intake one tooth

I've already created some of the documentation ... that shows the cam timing marks in their stock position as well as when moved one tooth.

I've also pasted a degree wheel onto a powerpoint slide and dropped the timing graphics on top of it, to see how these modifications to my 790cc engine will compare with the more conservative stock 865 cam timing (very close, it turns out).

Here's what I anticipate the three dyno runs will show:

- with the exhaust and intake cam timing changed, hp will drop off at higher rpm, but will exhibit more torque in the lower rpm range. The modification will reduce the valve overlap from 39 degrees to much less (9 degrees) which is nearly identical to the 865 engine. Since the 790 cams have somewhat more duration, the exhaust would open sooner than the 865 by several degrees, and the intake would stay open approx 10 degrees longer.

However, I won't know what these cam timing changes will do until I try it. I plan to schedule the bike into a small local speed shop for the 'baseline' dyno run sometime over the Xmas holidays.

The second run, with advanced exhaust timing, will take place later in the spring, after I pull the cams to correct valve clearances.

The third run with retarded intake cam timing, will follow.

I want to do this using an essentially stock 790 engine, except for the std mods we've nearly all done, like rejetting and snorkle removal, and the addition of TORs or some other aftermarket system. The key thing is that I want to make no other changes aside from the timing changes before each dyno run.

Back to my original question ..... if this comes to be, how can I post this info in powerpoint format to this forum? Or would it make better sense to have it converted to a PDF file which could be opened using Adobe Acrobat? In either case, is it possible to post such a file to this forum?

Bob

Bob

[ This message was edited by: ohiorider on 2006-11-30 18:40 ]
 

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Bob,

You would post a Powerpoint just like a pdf file. Upload to someplace on the internet and then use the URL function to insert how to find it.

Not everyone has Powerpoint so a pdf is probably better.
 

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I'm no geek, but I'd go w/ the pdf. It'll be smaller. Prob put it on a hosting web like you would a picture, then make a link.
 

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Discussion Starter #5
Allright .... PDF it will be, when the time comes. I'll use Powerpoint to create the pages (I used it for ages in a marketing job so I'm comfortable with it), but I'll convert the pages to a PDF document.

Thanks for the input.

Bob

[ This message was edited by: ohiorider on 2006-12-02 07:10 ]
 

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If you're comfortable with Powerpoint, you should use it to create the pages and then convert to PDF. But, in my (correct) opinion, it'll be b utt ugly.
 

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GeoDiablo, Powerpoint converts just fine to pdf in most cases. Although there's a chance some charts and graphs might get messed up. Is that what you meant?
 

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Discussion Starter #10
I'll make it pretty for y'all. (I can always call on my old friends and work associates in the Graphics Department to clean it up if I run into problems).

The content will take some time to generate, since I won't be doing the base level dyno run until the next warm stretch of weather. It's going to be one run at a time (1) stock timing (2)modified exhaust timing (3) modified exhaust and intake timing followed by updating the documentation. I stopped by the shop today and discussed the project and costs for dyno time with the owner.

Bob
 

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Discussion Starter #11
Is anyone else interested in seeing the differences various cam timing changes make to the torque/hp curves of a near-stock 790cc Bonnie engine in a controlled environment? (same dyno, same operator, same engine config other than valve timing changes)

I'm going to do it to satisfy my own curiosity, and possibly ( I hope) will end up with a bike that produces more torque and hp where I most often ride it, in the 3500 to 5500 rpm range. At that point, an 18T sprocket might work for me.

However, I won't know that I've achieved a positive end result without spending a fair amount of time retiming the intake and exhaust cams and testing the change on a dyno.

And when it's all over, it could be $150 in dyno time and nothing but data .... nothing to recommend.

Ahhhh, what the h***, I've got the time and the curiosity. I'm going to do it.

Bob

[ This message was edited by: ohiorider on 2006-12-01 23:57 ]
 

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On 2006-11-30 19:18, GeoDiablo wrote:
Definitely PDF… Powerpoint blows.
Power point can be set up to do a lot more than a PDF, but like it was set earlier not every one has it and a lot do not know how to use it.
 
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