Knutz- I will have to find blossom Tx. on the map. I would prefer to find the lowly 703's. lol

King- i provided the funds to dyno the 6 quads last week. It was not very $$.

 

<< A DS turbo on nitrous could easily win the next 4-Stroke Wars, or possibly even a Sparks 505EX on methanol and nitrous, who knows. I would really like to get one of the portable dyno guys out there and I know if there is a really good un-official show of hands two weeks before the event we can get one. If this happens, I would be willing to dyno the three fastest 4-Strokes there on my personal nickel. >>



I'm not really worried about the turbo's, but a well built motor with nitrous could do it. I guess Jeffinrivercity will have to get the juice dialed in befor February. Anything that I bring will be all throttle, no bottle. Maybe Jeff can take the &quot;open&quot; class, and I can take the &quot;modified&quot; class. [I can dream, can't I]

King, I'm perfectly willing to let you put any bike that I bring on the dyno. I'd post the charts myself, but the dyno I use can't make a file that I can post[files are DOS], and the printer is so light that I can't scan it. I know it sounds like excuses, but I'm perfectly willing to &quot;put up&quot; in this case. I'm dying to get Jeff's bike on a dyno again, but that will be up to him.

 

<< Knutz- I will have to find blossom Tx. on the map. I would prefer to find the lowly 703's. lol >>


Oh, come on, the 130lbs. owner of the 760 wants to play too. LOL

&quot;lowly 703's&quot;, Now your hurting my feelings[img]i/expressions/face-icon-small-sad.gif[/img], not really. One has cams and the other used stock cams, but they both run pretty well. Both customers called me back to tell me how pleased they were with them, but that was a while ago.

 

14mins: What was your dyno results? You said you dyno'ed six quads? I searched for a post on your results but didn't come across anything. Feel free to PM me if you would like.

 

14MIN show us the numbers.Your stats.don't say &quot;65&quot; anymore,why not?

 

Wow!
Just came ascroos this post!
Great info,but leads me to ask a question.....
With 105.5mm bore and 87mm stroke what rpm should I not exceed?
I have(in the past)run up to 10k,after the last tear down(to under cut the tranny)I noticed wear on the piston skirt(002 to 003)I replaced the piston,and looked over all other components,all looked fine.Was this caused by over revving? NOS?
I am very careful with the NOS(small doses)
With Pams calcs,I shouldn't exceed 9k?
Jeff

 

There are many causes of excessive piston skirt wear. For example, depending on how the load is placed on the piston, you may have a problem with the piston pin location. If the skirt is wearing heavy on one side, moving the pin slightly towards the wear side (within design constraints) could help reduce that strain on the piston and free up some waisted hp. Another cause of skirt wear is a short rod; however, rod length is a balancing act. As you increase rod length (improve the rod/stroke ratio), your rod load limits decrease (you must move your red line down).

Why do you need to rev to 10k??? Where is your power produced on the dyno? Perhaps you need to change the cam timing to get more of what you want at a lower rpm. Can you say BOOM!

 

Thanks Raptor720,
I will try and restrain myself(keep the R's down)
I never really intended to rev that high,but there have been a few times while dragging the hill,I will look down to only to see the tach bouncing off 10k......Doh!!!
The rod is stock(polished)
The wear was even on each side of the piston,there was no damage or scoring of the cylinder.

My dyno run showed my peak power at about 8200 rpms

Jeff

 

Talk to Don about your cams. You may want to try to change the cam timing slightly and see what happens.

 

WOW Jeff, If peak is at 8200, and you spin it up to 10,000, even when you shift you are still past peak power. Maybe we should hook up a shift light for you[lol]. The cams in your motor are degreed to work hand in hand with your head, so shifting the timing would end up with a loss in one range or another. The rod your running will help keep the motor alive, but please be carefull Jeff, I may need you in Feb [img]i/expressions/face-icon-small-wink.gif[/img].