1985 Kawasaki KXT250 Build Thread

[sjsst41]

I’ll consider this project “done” except I do need to dial in the jetting. I now realize it was a bad decision to use a Keihin PJ carb on the Tecate. The fit was great, but the idle being tied to the choke is flawed. Anyway the idle needs attention, and I assume I’ll need to fine-tune the pilot jet, at the moment and he trike runs well but the idle is not consistent. Anyway I am pleased at how it turned out, and I’m looking forward to handing it over to my uncle in Pennsylvania. The plan is to head back in August and deliver it then. Now I’m onto building the ‘86 ATC250R, with the goal to finish by August so I can ferry it back to PA for some trail action. Should be fun (as long as no one gets hurt)

[sjsst41]

Photo of the finished product ! Note I did install the “Tecate Uni-trak” and “250” rear fender graphics after the photo was taken a couple days ago.

[HondaRidr]

It looks great! Those PJ carbs are a pain. In my experience the pilot has to be a little too lean to get a decent idle. I still run one (it is about to get replaced though) and just deal with it not idling.

[rpeters]

I probably have a nice original carb. I have fork tubes that are probably good.

As far as the rear suspension goes, if you plan on hitting any bumps or doing any jumps, you need to change the rocker, dog bone, and shock to an 86 setup. It bolts right in and I have a few of them I would sell one if you want the rear to work somewhat on anything other than flat ground and not bottom out when you jump more than 2 feet in the air.

Also, the 86 shift mechanism is interchangeable and works better. I may have one I would sell, but you can find them on Ebay.
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[legacy51]

Nice job! It turned out to be a good looking trike. I've never seen a bad looking tecate though

The 84 rocker isn't bad at all. It acts like a no link swingarm because it's not really progressive. It's really nice because it makes the rear end super predictable. It just doesn't do so well on bigger hits which most trike riders don't big jumps anyways. I changed from 84 to 85 on my tecate and I preferred the 84 for general trail type riding. I could the whoops really hard too with 0 bucking. I really liked the 350x rear suspension too so maybe I am a no-link kind of guy. It all depends on what you like and how you ride.

[HondaRidr]

What do you mean the 86 shift mechanism? The shift lever or something else?

[sjsst41]

Thanks for the offer on parts rpeters, I’ll pass on the suspension though as I’m thinking this trike isn’t going too see much air time, my uncle is 65 now and probably shouldn’t be launching it, although he’s still a wild man. I’m looking forward to getting out on the trails with him (damn, reliving like 40 years ago). I just hope “no one” gets hurt. But let me know how much you’re asking for the carb. I’m going to try and improve the PJ, and might consider buying a PWK - which I like (I installed one on my ‘83 CR250 race bike & it is a nice carb to dial in)

[rpeters]

What do you mean the 86 shift mechanism? The shift lever or something else?

shift shaft assy and shift star . i have all the pats needed for sale.

[rpeters]

Ok I will take a look for the carb. The stock carb works flawlessly on a stock or near stock bike . if you go to an aftermarket carb the best one is an old school mikuni round slide. all these fancy azz $400.00 carbs will absolutely not get you to the finish line one iota so0oner.

[sjsst41]

Delivered ! Unfortunately the new owner (my uncle) gigged his ankle a few days ago, so we were not able to ride, I did leave the 250R at his place, so when I’m back in October we should be able to get out.

[sjsst41]

Both trikes

[sjsst41]

Ok - so this Tecate RIPs, I did some riding around my house before packing it up and delivering to Pennsylvania, my uncle finally took it for a spin and commented on how intense the power delivery is. I noted the bottom end is mellow, starts to pull when you get into mid-band and has a “healthy” top end. Probably great for the track, but not the best for trail riding. Any recommendations on how to re-tune that motor to offset the top end while improving bottom end performance? The piston is maybe .010 or .020” over, Boyseen Rad Valve installed, DG pipe and Answer silencer, stock ignition with a Keihin 34mm PJ carb. I started some online research, but currently coming up empty. Thanks

[sjsst41]

One thing I thought of is to add the heaviest flywheel weight I can find. Anyone know if that exists for these older motors?

Edit: looks like Stealthy makes one for the ‘83 KX 250 motor ! So I assume it’ll fit the ‘85 Tecate?

https://www.steahlyoffroad.com/kawas...eel-weight-603

[Footy]

One thing I thought of is to add the heaviest flywheel weight I can find. Anyone know if that exists for these older motors?

Edit: looks like Stealthy makes one for the ‘83 KX 250 motor ! So I assume it’ll fit the ‘85 Tecate?

https://www.steahlyoffroad.com/kawas...eel-weight-603

This seems like a great place to start!

[HondaRidr]

The 83 kx250 flywheel fits on a tecate crank but the stock flywheel is much larger diameter than the kx. You could go back to a stock headpipe or even smaller carb possibly. Your build is already fairly mellow.