Dynamometer Appointment Scheduled

z1kzonly wrote: Go with the comp baffle! Just to enjoy the sound! Nothing like those old 1 of a kind sounds of a Z1-KZ engine with an open pipe.
I love this video, it's old from 2010.
Watch this and get your adrenaline going!

I'll bring a couple things along: Competition baffle, .07 air jets, shorter stacks, ear-plugs, a couple tools, camera, adrenaline, etc...

:woohoo:

KZB2 650 wrote: Cool lets make it a contest...... could be a mile off but I say 105.5 HP and am hoping for more.

According to the 1982 KZ1100A-2 FSM, the stock engine spec was 100 HP

The head, cam, carb, header, and ignition upgrades can only help...
Perhaps I should bump the rev-limit to 9.5 or 10

Dave remember that's 100 CRANK hp.
I did my 650 with the worn out 83 GPz750 motor with VM29's and an old Kerkerit made 76 at the tire.
Spec's list 87 at the crank stock.

zukdave wrote: Dave remember that's 100 CRANK hp.
I did my 650 with the worn out 83 GPz750 motor with VM29's and an old Kerkerit made 76 at the tire.
Spec's list 87 at the crank stock.

Ok then...:S

I'll post the result, and perhaps learn something of the significance...:whistle:

daveo wrote:

zukdave wrote: Dave remember that's 100 CRANK hp.
I did my 650 with the worn out 83 GPz750 motor with VM29's and an old Kerkerit made 76 at the tire.
Spec's list 87 at the crank stock.

Ok then...:S

I'll post the result, and perhaps learn something of the significance...:whistle:

The dyno-operator (Scott) suggested the main jets were way too-rich by two-three sizes, and that lowering the needles might help. :whistle:

After returning home, I lowered the main jets two sizes to 127.5 to lean-out the mid-range, which Scott advised "was off the charts".
He also suggested that "if correctly jetted, the engine might gain 5 hp."

The test indicated the peak HP registered at 9K rpms. was 90.2 at the tire.
So, assuming an "approximate 15% hp. drop from the engine", KZB2 650's guess was pretty close.

Sounds about right for a shafty.
Steve

SWest wrote: Sounds about right for a shafty.
Steve

Dyno pull printout for review and comment:

Nope I was off...... I was hoping for 105 at the wheel with your mods but with the leaner mains and the comp baffle sounds like you could be at least at 96-97 or so.

You've convinced me to dyno mine but probably won't be for another month or so...... I may check it with the 24s and then with the 29s just to know for sure what the power diff is. Larry C was nice enough to write me back and he thinks I could pick up 5hp at the wheel and have a stronger mid range with the 29s so that's got me a little motivated.

On reading that fuel/air chart I sure wish some in the know would chime in..... (I may start a new thread on it if we don't get much explaining of it if you don't care) ........I take it you are shooting for around 13 to one on the mid to upper range and his 10 to 10 and 3/4 shows way too rich ?? And does his 2 to 3 thousand range show a little rich too and also what the 4 to 6 thousand range for the needle being too rich by showing a little under 12 to 10 to 1 ? I'm betting I'm on the rich side too and want this to point it out for real. In the add I'm looking into they say they will check it out and recommend changes to free up more power but I'd like to at least look a little like I know what I'm doing.

Anyone, please feel free to build on my shaky base, and don't hesitate to add anything you think may help to improve my footing. I possess a weak insight for fine-tuning, but will always endeavor to make it better, given a recommendation or two based on knowledge attained through experience. That dyno run was probably the best $50 investment I've made in awhile.

I just want to ride...especially when this bike runs better than I can make it.

That is a good graph, it looks to be running fairly well.
I have done a bunch of runs and this is what I know , the operator plays a big roll and good one is worth his weight in gold!!, the dyno plays a big role from the charts it looked like a dynojet 250i ???

Dynos like to read rich so be careful to not get to lean general street driving is a bit different and being a bit rich isn't a bad thing…but just a bit.
Use the same operator every time you do a run. I watched two different guys dyno my GS back to back with a big difference…. the "kid" who did the first run rolled off the throttle just a bit at the end of the run and then rolled it back on and it messed with the AF reading and the HP reading. WEIRD but true

Way back in 2011 the same guy (Scott) ran a dyno-pull on the bike, when his setup was at a semi-secret location in the Grand Rapids, Mi. area. At the time, he was the only guy around that I knew of with a dyno, and was good at what he did even then with what he now considers outdated technology by today's standards. That run was done before I started changing things on the engine, and I thought it was running better than ever...even back then. :lol:

I have a copy of that result, which I may post for reference...mostly stock then.

The charted HP was way-less then than it is now, and it may even have been running rich then too. That was with the old J-head and standard camshafts, typical of the J-engine from 1981-2004 I believe...that's twenty-three years, guy's. It's no wonder ebay is such a great source for parts to keep these bestial-animals alive. :evil:

Figured I'd run premium for a change yesterday, but after checking the spark plugs that gas was drained out and put in my truck. For whatever reason, this bike still prefers regular gas. The more expensive fuel stuff just works to make the spark plugs black, and doesn't make the bike run better...but the old truck likes it. :S

While cleaning the black spark plugs, it occurred to me to check the #3 plug wire with my cheap multi-meter that I finally broke down to purchase a couple years ago.
That #3 cylinder had not fired properly for a long time...it was evident by how that header pipe hadn't blued like the others.
I've been using Accel U-Groove non-resistor spark plugs with NGK resistor caps and copper-core wires, and just now discovered why that #3 spark plug insulator was persistently lighter than the others...

Well, lo and behold that #3 resistor cap was not working properly, if even at all. lol
Now I figure that out , right after the dyno pull...of course... Yep, that's me folks...the one thing that burns well for me is money!!!

Maybe that single deficiency was robbing my engine of power , just when it would have been handy. And oh, it might even have contributed to my poor over-rich condition, since that cylinder wasn't burning the fuel...well.

Please pardon my rant. :evil: :evil: :evil:


:whistle: