Buzz Killl?

[Ben70_imp]

Thanks PD. I will be checking the pulse width question tomorrow, I believe. A friend with a shop is going to "dig out" his oscilloscope. Hopefully it hasn't fossilized.

Ben

[Ben70_imp]

Finally got the injector pulse width checked. The pulse width on 1 and 4 injectors is identical, so with that and ignition timing being the same I will see if the cam man has any input. Also seriously considering a PC5, I feel like it is still lean with the Guhl flash. Should probably dyno it again.
Huge surprise that the injector pulse width and ignition timing are the same! I guess the only thing they did was change the cam lobes. There must be a cam grind that will end up as good as stock.
I feel like it's not worth this just to kill the buzz, but I am having too much fun. It's a little disappointing that this information is not available from Honda. They are pretty guarded with their theory information on their cars, too. At least last time I tried.
I haven't really trusted them since my cooling fins didn't clink when I was walking away after a ride.

Ben

[PowerDubs_imp]

Throw a 2nd intake cam into the exhaust and see what happens??!!

2014 HONDA CB1100 CAMSHAFT INTAKE https://www.ebay.com/itm/401958936093


Sent from my iPhone using Tapatalk

[Ben70_imp]

That may be a steal for this kind of a project! Don't bug me , I'm looking for a problem to fit my solution.

Ben

[Ben70_imp]

OK, as it turns out, swapping the exhaust cam to the intake side does work quite well, you just have to install it properly.
After determining that the injector duration was the same, and the ignition timing was the same, I was getting frustrated that the performance wasn't closer to original on the dyno.
I had asked a cam man, Joe at American Custom Cams in Glendora CA, to take a look at the intake cam. I told him I wasn't going to make any other performance mods and he figured he could grind it uniformly and I could shim it to specs.
So I got the cam, which looked like a regular exhaust cam but with smaller lobes and when I went to install it I noticed that I was off a tooth on the cam timing.
If you are going to screw up, do it in front of an international audience on a 5000 member forum!
So of course I wanted to fix it and see what happened right away, but I figured just to see I would try the reworked cam. It worked OK, but I could tell when pulling some of the local hills that it was lacking power to the point that I didn't bother with a dyno run. Nothing against Joe's work, and I would go back to him with an exhaust cam to try to "open it up a bit" for install on the intake side, but he didn't have a lot to work with for just a regrind. I may not be messing with cams anymore though, at least for a while.
So I put my new exhaust cam back in on the intake side, properly, and right away I knew I was close to my stock setup. Ran a couple tanks of gas through it and got 44 mpg, which is about normal for me. The pull at low to middle rpm felt strong and I was eager to see what the dyno had to say.

Hope you can see it. The red line was today, the other was the original. I am running a full Yosh exhaust, and the only difference was I had a Guhl flash performed since the first run.
So the limiter was in effect on the original run (all in 3rd gear) and the hp and torque at the upper rev limit would have probably been close to identical otherwise.
However, both hp and torque are noticeably improved in the low to midrange.
It can be felt and I am Jazzed. Don't know how much was attributable to the flash. It is running less lean in that range now as well and I am sorry I didn't do it both either before or after the flash so I could know exactly what the difference was.
In any case I am happy with the result. I plan on no further performance mods. I know PowerDubs opened up his intake and had other fueling enhancements, but he was after improved performance.
As it is I plan to re-install my 19 tooth front sprocket, and with all that new torque I think I will try my 37 tooth rear again. I plan to do a few trips this summer and the mileage/range increase will be nice to have.
I went about this backwards on a few fronts. I should have verified the ignition timing and injector pulse to be the same, instead of assuming it. And of course it would have helped to install it correctly the first time. And I would have done the re-flash before or after the cam results were in.
But in the end it can be done, with an increase in torque and hp where it is usable. Also reduced buzz, and a comfortable feeling across the rev range.
My apologies for the screw-up on the cam timing, I can't believe it was so obvious when I took it apart.

Ben

[max]

Ben that's a great ending, like many others i have followed your work and although i can't say i understand all of this i get enough info out of it to understand what's going on, i do have my limits.

Finding things like that are normal with trying something new, mister Honda made a great deal of them and he learned from them as did myself, getting the result you want or better is the real reward as far as i can see.

To be honest i have not experienced the "buzz" that you mention, maybe that's a good thing since it now doesn't bother me sofar and also do you happen to have a picture of the installed cams?

[Ben70_imp]

Sorry, max, no. But they are both stock exhaust cams.

Ben

[Cormanus]

I suspect I understand a great deal less than max, but congratulations Ben70. I'm pleased you sorted the problem and got an improved result. Settle now and enjoy the bike.

[PowerDubs_imp]

Good job! Your fueling is much better, and the tq gained back is impressive.

Did you re-shim when you adjusted the tooth?

I almost wonder if I mis-timed as well since my cams didn't do much...they really should have.

[Ben70_imp]

I re-shimmed all along. I suspect when I made my final shim adjustment the first time I had the slack in the wrong place when I put it back together, I don't know. I do know since then I make one last check with the tensioner engaged before putting the cover on.
I wonder what your setup would do with a non-staggered intake? Seems to me if the ign. timing and injector timing and pulse width are uniform, uniform cam lobes could help?
I am surprised by the torque, and I wonder how much the flash had to do with it.
Thanks for leading off in this direction, I am enjoying it.

Ben