ARRRRG ! Darn cheesy thin throttle cable !

[islandbum]

hey Dazo
here you go a bloke from sydney has a efi and has done the tune boy go have a read + it shows a dyno graph
http://www.bonnevilleamerica.com/forums/showflat.php?Cat=0&Number=339292&page=0&fpart=2&vc=1

 

[CarlS]

Good post, Islandbum; thanks much. :y115:

 

[dazco]

Hmmm...thats not very good. Guys get better than that with carb'd bikes and those mods ! 56 is probably about what the rear wheel HP should be stock. It's 61 at the crank stock. So getting 56 rear wheel with those mods is actually pathetic. This is bad news for me. :sad: Sounds to me like the bikes are NOT actually a 7 HP improvement over the carb speedys as the specs show. Could triumph be lying about this i wonder.

 

[CarlS]

Different dynos will give different results. I can dyno my Bonnie on one dyno today and a different one tomorrow and the results will be different. The graphs will have the same shapes; but the figures will be different.

 

[dazco]

i can see maybe 3HP difference on a bike that hovers around the half century mark, but thats just way too much. If dynos are that far apart i see no point in posting them unless everyone uses the same one. I'm not doubting you in the least, just remarking on how bad that is. I guess the only value is determining gains on your own bike between mods.

 

[CarlS]

A lot of things cause the variation besides the individual dyno. Temperature and humidity are big factors. That is why the racing teams do their dyno runs in a controlled environment so as to eliminate those variables.

 

[dazco]

That seems to make them even less worthwhile because if thats the case you can't even use it to see what improvements you made with mods unless you record the day's temperature, humidity, etc, and do your next dyno on a day with the exact same weather. that leaves one last use....to tune the bike, which is of course the main purpose of a dyno even tho it seems most use it to just get numbers. if i were going to dyno my bike on a regular basis i'd go to the trouble of finding one in a controlled environment as you described to be sure.

 

[CarlS]

You are correct. But keep in mind that the shapes of the power and torque curves will be pretty much the same; it is the numbers that will vary.