TOPIC:

I got rings for about $12 a set. Might as well do the valve guide seals too.
Steve

+1 on what Steve said. I always buy 1 extra set of rings just in case I get a little over zealous and break an oil ring. Hone, rings and Viton valve seals is always a good idea. Like you said, your already in there. If you need gaskets and stuff search SWEST's " good guys" post for folks we have used for parts and service.

Steve- Do I just get in contact with Wiseco and let them know what I need? Valve guide seals were done when I rebuilt the engine in the first place- so they've got only 3,000 km or so on them, maybe not even that. Is it still worth doing then? Yeah, I figured I might as well freshen her up as much as I can

The old seal set was Athena brand I think. Honestly, it's low quality stuff... my lower cylinder seal started leaking not even 500km in. Thanks for the tips, guys. I appreciate it

I would put in Viton seals while you have it apart. In my the good guys thread are suppliers for gaskets and for Wiseco pistons. They may have rings. Wiseco charges more if you deal with them direct. Worth asking though. Closed mouths don't get fed.
Steve

Sounds good to me! I'll hit ya up when I have her apart if I need anything. Thanks again!

Devin

So it's been a while since I posted up here last, and I've started tinkering on the bike to get her tuned up for when it finally warms up here. We're still dealing with some snow on the ground, and overnight lows of -15 celsius, so I can't really bust the bike out quite yet. There's way too much sand on the roads from the snow plows, so I still need to wait another 3 weeks or so before really getting out for a ride. We had some warmer weather 2 weeks ago where all the snow we had melted, and I was able to fire the bike up and go for a spin.
I did get the fuel petcock diaphragm changed out last fall, and that sorted out the rich issue on cylinder 2. I just have to wait for it to warm up a bit before doing a good pilot circuit tune and vacuum balancing again.
In the mean time, when it's been warm enough, I've started to get the little windbreaker mounted up that I bought a few years ago. And of course, with anything "universal" comes alot of tinker time and modifications to make things work right. I started off by shortening the headlight ears up by around an inch and a half. Re-drilled mounting holes for the light, then started to figure out the windscreen mounts. I had to cut some steel off, bend the bracket in a few spots, but I think I've just about go things sorted out for the time being. Here's a few pictures of the screen roughly mounted up, I just have to add some rear mounting plate support bolts to keep it from bending back in the wind on the road. I think it adds to the overall look of the bike and completes the street fighter look I was aiming for. Plus, it will hopefully add a little bit of a wind break to the ride












Devin

Nice work Devin !

Keep it up

Arnold wrote: Nice work Devin !

Keep it up

Thanks Arnold! Just a few small things to tinker at before I think she's done for now.

congrats devin.
had a blast following along.
now get out and enjoy the fruits of your labor.

leon

Thanks Leon! Unfortunately, she's not 100% there quite yet. I still need to tune up the carbs, and then get the dyna ignition on. At some point, I'll be fabbing up an exhaust that gives me more than 3" ground clearance so I don't jam it into the pavement so much. But for now, she's ridable and a blast at that!
Also, the snow isn't quite all off the ground here yet, and the roads are still pretty sandy. I figure it will be another 2-3 weeks before I have the bike on the road steadily.

Devin

Alright guys, so I'm having a head scratcher moment here with the bike. So since I got that petcock issue sorted out where it was pulling fuel through the diaphragm and causing cylinder 2 to run rich, I went up a size on the pilots to a #17.5 and tuned the pilot series with my Colortune unit (absolutely love the tool). I got every cyllinder dialed right in (nice blue flame, caramel to tan color electrode on visual inspection) EXCEPT for #2 (running the petcock vacuum line). The bike's engine specs are as follows: bored to 720 forWiseco big bore kit, Dynajet stage 3 jet kit, pods on all carbs, 4-1 pipe off 2002 Z750 with Yosh can, no valve work (cams, etc), soon to go on Dyna ignition. The cylinder isn't wet fouling like it was with the leaky diaphragm, rather dry fouling like there's excess oil on that cylinder. No matter how far out I turn the pilot screw (at 3 turns now, pretty well the max before it falls out), she still burns orange (rich) on that cylinder. When I rebuilt the engine around 2000 km ago, I had the valves professionally re-faced to seat into the head properly. The valve seals were replaced at that time as well. The coils were also replaced, and there's even spark and good blue spark on both cylinders 2-3 from that coil.

Last year I took the carbs out and did a full clean on them multiple times- soaked in cleaner, passages cleaned with a wire/blew air through passages while plugging other ones to increase pressure in that passage.

With that in mind, I'm kind of stumped as to what the issue could be. I'm not overly worried about it as it really doesn't affect performance that much. The bike fires up super quick even when it's "cold" (10 celsius, 50 fahrenheit). I would, however, like to get this issue sorted out if possible so that I have a nice burn across all 4 cylinders.

Does anyone have any ideas as to what could be going on here? I'm thinking some of these ideas could be what's causing it:
- oil control ring is worn/seated funny from when that cylinder had the leaky valve with too much fuel
- leaky valve seal
- slightly blocked air passage on that pilot

Any and all input is appreciated! Thanks guys!

Devin

Hi Devin,

This is really tricky.
I had one cylinder running cooler than the other three and could not seem to sort it out. Changed the intake cam and the issue swaped to a different cylinder. I finally found a set up where the difference was acceptable and I let it be.
Guess things will change when the engie i fully broke in.

With all the mods you (we) done it´s extremly hard to determine how they correlate together.

Is the Engine run in after rebore ? Have you checked compression, vale clearense...?
Have you measured the temperature on the exhaust pipes to compare the four ?

I would run it as is and revisit the issue after the summer. I honestly dont think the engines were perfect even when they left the factory.

Sorry I can help