Help! Tri-Z guys...

[Racerguy381]

Well Im still having problems if anyone has a CDI box I need one. The stator didnt fix the problem and Im still stumped on anything else.

So I have ran into a brick wall...Dammit I have been up and down with the jetting but it seems to have the same senario. Runs but craps out on top. My questions are if you have the same set up with a 38mm round slide are you still running the fuel pump and what needle seat# are you using. Next is who has a manual for an 85 Z that has the test specs for the stator volt regulator and coil. Any info is better than none considering I work at a Yamaha shop an we dont even have a manual that far back. Thanks guys :beer

[Yamaha_Rules69]

Do a search near the top right of your screen for REPAIR MANUALS. I know for a fact there is one for an 85 tri z, because I just looked at it yesterday. Good luck.

[MonroeMike]

http://72.52.143.80/~trikes/tri-z_250_servicemanual.pdf

[DeePa]

As far as your fuel pump question, try it with a full tank of fuel and see if that helps.

Rebuild kits for the pump are CHEAP and its easy to do. Its a great piece of mind for 20 bucks.

As far as you needle and seat question, id be more inclined to mess with main jets first, then once you get it close and its still not perfect, mess with the needle and the different tapers and such.

Just do once change at a time and write down everything you try.

Here are your specs:

CDI Magneto Source Coil: Black to Brown Wire 315 ohms +-10%

CDI Magneto Pickup Coil: White/Red to Black 10.7 ohms +- 10&

Primary Coil Resistance : 0.79 ohms +- 10%

Secondary Coil Resistance : 5.9k ohms +- 10%

There wasnt anything about the voltage regulator in there, but all that does is keep your lights from blowing, so if they arent getting purple and blinding, you should be ok there.



Tri-z's are somewhat known to rattle stuff loose. I had a z that ran like crap because the 2 bolts (that someone didnt loctite...me) that hold the stator plate on the case loosened up and the trike still ran but didnt have the right revs and i finally lost spark when it came totally loose and was eaten by the flywheel.

[Racerguy381]

Thanks DeePa, I have been up down and even sideways with the jets... lol I have already rebuilt the fuel pump so I know its good. Think I will check the electical next just to be sure Im not chasing my tail for no good reason with the fuel issue. It is possible though cause if I pinn it on a bumpy whooped out road it seems to get better an want to rev.... which makes me think fuel... you see.... ya its just irritating me now. Thanks again

[Dammit!]

Make sure the float is adjusted right. It might be low which wouldn't cause a problem at low speed but the more throttle you're giving it, the lower the fuel level in the bowl will get. If it's too low it can definitely cause a similar symptom.

[Racerguy381]

Ok so Im pretty sure gus not the carb now. I had a39mm air striker off a CR so I threw it on to try it. Same problem cuts out on top but runs great bottom to top. I even checked the stator test specs all passed. All the fuel lines and tank return lines checked out as well... So it could be stator still just a bad winding or CDI box is all I can think of now. Anyone know whats more common on these?

[Mosh]

Mine was doing something very similar to yours.
Especially if the trike got wet.

I had spare parts, so First I unpluged the on off switch and ran it. No help.I saw one Z a friend had busting up on the top,and a piece of steel would rattle in the switch and create a slight ground.They will run with the swictch unplugged, they just wont shut off.

Then I tried a different coil, no help.
Then a cdi box.No help.
Finally, I threw a stator in it.
Fixed it.
I did the stator last cuz it took more work to change..LOL

I would say coils are more common.They crack at the housing and arch to the frame.
But it sounds as though it may be a stator.They can test good with resistance, but put out weak voltage under high RPM, that you could only find with a ocsillascope.

Dumb question, but you have tried a new plug right?

[Bryan Raffa]

check the orange wire where it comes out of the coil.. they like to crack there and jump spark there

[Racerguy381]

Ok so who has a good stator or source coil? and how much. I have a friend checking to see if he has somthing that will work off a IT250 not sure if he does yet though.

[hondatrike0]

im just joining the topic but i just built a tri z with a powervalve motor. craps out on top , 1st check to make sure your power valve is opening all the way, second did you use the stock fuel pump?if so replace with the mikuni jet ski pump, its like 21.00 dollers. third put an inline spark tester in it and rev it up were it cuts out. if you see a drop in spark than go that way. if that is the problem hit me up. if you pay shipping ill send you the electrical parts. 4th crank seals will make it run weird not to mention in some casses crap out on top.....

[Bryan Raffa]

whats your plug look like..

[Racerguy381]

I know its not crank seals cause I just replaced all the mains and seals when I did the PV swap. It is the stock pump but I put all new diaphrams and gaskets in it. The PV does open all the way I already checked that too. As far as the plug goes its never really changed much in color no matter what jets I throw at it. Right now it has a 40 pilot and a 310 main but still is dark brown on the verge of black... This is whats making me think its electrical cause it will fool you into thinking its bad jetting when its really loosing voltage at the plug at high RPM. Plus it does it worse under a load.

[Racerguy381]

Noticed tonight that the pilot light checker is cut out of the harness. All the wires are there. Would not having it hooked up effect it in any way we have talked about. Next would be does anyone have one?

[Mosh]

Your Tri-z will run fine with out the checker bulb box plugged in.

When you went thru the motor, did you set your stator plate at the middle of the adjustment slots?

[Bryan Raffa]

start leaning it out with main jets..its way fat.. they will studder if there not close..

[Racerguy381]

If I remember correctly I set it one notch retarded for more mid an top power.

[Racerguy381]

When I ran the 310 in the mikuni it seems to detonate before wide open with the needle in the 2nd clip from the bottom

[Bryan Raffa]

detonate.. and your plug is still black?..hummm

[Racerguy381]

You see why Im pretty confused now lol... This is why Im thinking its electrical since it keeps producing the same symptoms with different carbs and jets. I just foot have a cdi box or stator to swap and try.

[Racerguy381]

Still looking for a good stator CDI box and also a on off switch the red switch part broke when I took it off to insect it.

[Racerguy381]

So I got a replacement stator but it still hasnt fixed the problem. Anyone have a CDI box? Thats the only other thing besides coil or the jetting is completly off the chart. Anyone got any ideas now?

[Racerguy381]

:confused: Im baffled.... I have changed carbs, stator, CDI, kill switch, jetting, fuel pump, spark plugs.... It still wont rev all the way out on top. Runs great just revving it but if you hold it wide open it will cut out..... Anyone else got an idea???

[Bryan Raffa]

lean it out:twisted: one jet at a time.. till the studder stops.

[Racerguy381]

It seems to only do it if you hold it wide open for a couple seconds... it like raaaaaa......ahhhhhhh.......ahhhhhhhh.......ahhhhh hhh..... lol:wondering