Rear Wheel H P

[subike]

Interested in your views on HP for the xs
I was at a motor cycle race meeting this past sunday
There was a rolling road dyno there, being operated by a local professional motor cycle exhaust manufacture specialist.
He is well Know in NZ and his workmaship and tuning are second to none.
He was an assistant to John Britten, who built the Britten race bike that won the battle of the twins a daytona twice.
So his creds are real.

Now
I put my 74000k 79 XS Eleven F on the dyno, It has a 4 - 1 exhaust.
The dyno reading was 86HP @ 7800rpm . At the rear wheels
Is this reasonable or should a tune and tickel improve this.
Am interested in your results as a comparison.
Also what plugs should I be running withon Lead free petrol.
What should the timing be statically set at as well.

[subike]

I have checked out the plug thread so, Got that info now,
interesting reading for sure

[GNEPIG]

I think the you have done pretty good with what you have.
Here are some other Dyno results to compair yours with:
http://www.xs11.com/forum/showthread...t=dyno+results

BTW welcome to the site. Now you will need to post a picture of your great machine for the rest of us to enjoy.

[Yamdaha]

oh happy day....we just ran my 78e on our dyno here and pulled 94.93hp @ 8100 rpm with 69.6 lb ft tork.....
4:1 "something" exhaust, stock air filter, and home made jetting.

[Yamdaha]

oaky, help a sorta newby bro out...my dyno chart also has a dip at about 4500-4800 rpm (the linky chart shows on as well). and it almost sounded like a miss or hiccup passing thru that rev range. any insight?

[GNEPIG]

Does your dyno sheet show an air/ fuel graph (usually printed across the bottom)?
This graph will tell you where your air to fuel ratio is at certain RPMs and will help you decide which direction to move your jetting to help straighten out this dip= there will be a corresponding dip in the fuel line about the same place as the dips in your horse power and torque lines.

I'm betting your running too rich in these problem RPMs.

Something easy you could try is to remove the lower air box/ filter and test ride it without it. If your problem gets better then your running rich.
If it gets worse, then you're running lean.

Good luck and keep us posted as to how you do.

[subike]

after the dyno
i removed the std air box and drilled three 1'' holes in the bottom of it to increase the air flow.
This has helped the engine to breath better and have found that it is now smoother in the pull from 3500rpm.
Other than that, new plugs and setting the timing off the cam after doing the shimms and adjusting the cam chain seem to have also smoothed out her power .
Have yet to put her back on the rolling road to see if there is an improvement......I bet there is

[Yamdaha]

Originally posted by GNEPIG
[B]Does your dyno sheet show an air/ fuel graph (usually printed across the bottom)?
This graph will tell you where your air to fuel ratio is at certain RPMs and will help you decide which direction to move your jetting to help straighten out this dip= there will be a corresponding dip in the fuel line about the same place as the dips in your horse power and torque lines.

hp drops around 46-4800 and the a/f drops right after at 5100, then both climb from there. i'll drop the lid on the air box and re run it.
thanks