250-500cc Next Project - 6 speed WR 250

[msmith345]

Ok, so I guess I didn't reply Friday night.

It was not running in reverse. I advanced the timing to 11 degrees BTDC (the high end of the recommended timing) and the noise level dropped to normal. Idle is still slightly high, but that one is fuel related as I was able to adjust.

I did get a nasty kick back prior to getting it all adjusted. Probably the hardest one I've ever had, needless to say, 3 days later and my ankle is still swollen and sore. The weather is breaking, so hopefully I'll be able to pull it out of the garage and do a test run around the neighbor hood later this week. Assuming the swelling goes down, or I can kick it over with my left foot.

 

[MOTORHEAD]

Well, that's good to hear. Still think you should invest in the timing light.

 

[msmith345]

Well, that's good to hear. Still think you should invest in the timing light.

I have access to one, but I really don't see how that would be of any benefit. The way the PVL is setup, the timing sensor and rotor are both marked already - this is where any slop would come into play, as you visually line the two, but you wouldn't be more than a fraction of a degree off if you were paying attention. Then on the dial I basically have 8 ticks per degree I can accurately measure. So, it's not a matter of not knowing when the spark is firing, it's a matter of knowing when that firing should happen. In this case, it's basically, "on a generic 250cc 2 stroke, you'll want to have it somewhere between 9 and 11 degrees BTDC, but you might need it more or less. Oh, and don't screw it up or you could melt your engine."

But, if you can explain to me where the value and utility of the light would benefit this application, I'm all ears. I just don't see where the width of a paint brush would give better results than a score mark and a precision measuring device.

 

[MOTORHEAD]

Ok, maybe you don't need one with that ignition.

 

[2premo]

the biggest advantage to a timing light is to see what it's doing in the real world
I installed an ignition years ago that had an issue of being out of clock, I set it according to the instructions but it was built wrong
if you are not POSITIVE it is a cheap check for sure

 

[msmith345]

Well, the saga continues.

Finally had a decent weekend here, so I spent it in the garage. I'm racing a national enduro on the 23rd and have to have a bike ready. Never mind the fact that it's been 5 months since I last road in the dirt.

So, I started putting the '92 all back together as a back up bike. Ran into a couple hiccups on it. I'm going to need a throttle cable, and I'm going to have to find the Keihin AS that I took over to my dad's house. Put a new cheap-o front tire on and essentially got it ready to rock with the RB modded Mikuni. Fired up fine, but I just don't trust the Mikuni.

After I got as far as I could on that, I pulled the 250 out and went through the stock ignition system. I found a spot of wire that could have rubbed enough to cause a short so I figured what the hell, and fixed it up, pulled the PVL system off the bike and put the stocker back on. It didn't want to at first, but it eventually came to life. With a raise idle, so I have more Lectron tuning to do as I'm way off how it was originally sent and not sure what that baseline measurement was. So, I think once I get the carb back to sorted, I will run a full test as well as I can on the stock ignition to see if all seems good. If it doesn't check out, I'll drop the PVL back in. With the carb sorted, and a baseline on the timing, it should all sort out pretty quickly.

I'll then just need to pop the dent out of my DEP pipe and get my spark arrestor re-packed (because my PC setup doesn't have a SA). Then I've got virtually every bearing on the bike arriving Thursday and I'll be replacing all of those. So, with any luck I should have a two bikes ready to take out for testing this weekend before driving 12 hours south next Saturday.

With 3 enduros and 1 harescramble in a row starting the 23rd, I'm going to make sure both bikes are fully ready because it's go time. Busy busy busy, top add to it, my brothers WR125 had a stuck ring Sunday with no compression, that he raced anyway, so I have to go through that, and a buddy's main bearings went out in his RM250. So, it's going to be a super busy week in the garage. And all I can think is I'm glad it's not -4 degrees anymore.

 

[msmith345]

Well, Lectron is sorted. I discovered an air leak in the union. That explains why no matter how rich I turn it, it still acted lean. Reset it to right about 49.5 mm and 1.5 turns out on the screw and it was good. Might go a bit leaner tomorrow and call it good.

Took a test ride around the streets of suburbia tight at dusk. Clicked through all 6 and was giddy. I may need to gear it down just a bit. But I'm pretty happy with the initial ride and I think it's going to be excellent for enduros. This thing revs much more quickly than both the 300 and 360 and just doesn't compare to either in torque. I'll test it out this weekend, but it should still have plenty for the gnarly, without wearing me down on a long race. It reminded me of my old 200 a bit. More torque but it's going to be a grant and rev bike for sure.

 

[msmith345]

Well, issues continue. Turns out the Lectron adjustments are still off. I've spent the last week trying to get it square. Currently, it starts and will run great with the choke on. Turn the choke off, and it runs at a good idle for maybe 20 seconds before sputtering out. What was happening before was it would start and idle, but had a big bog if I tried to ride it and would barely run well enough to get rolling.

This is a bit frustrating, as I'm thinking this is going back to being a ignition issue rather than one with the carb. A bit of a bitch because I've got several things at play. Questionable stock ignition. PVL ignition, where I need to have the jetting squared to sort the timing, and then the carb where it might be set fine and it could be completely off.

Fun stuff. I need to get this running in the next couple days as I have a bunch of bearings to change out yet, and have to roll out around 5 AM to make tech inspection at the NEPG... Agh.

 

[juicypips]

Email kelly and get the base settings fir the lectron
Leave them there untill you fix your ignition issues.
If i was anywhere near you you could swap parts with me till you found the
Culprit, anyone here close to msmith???

 

[msmith345]

I'm going to go over to my dad's and strip his 300 ignition more than likely. I really don't want to as he has maybe 25 hours on it, but I think I'm out of options. Hopefully, I can just swap the Ducati CDI/Coil unit across (his is an 11). And hopefully there's not something hosed in mine that will fry his. Shop opens tomorrow, I'll see what they can find as far as any ignition.

 

[msmith345]

For anyone's reference, the as shipped setting on the 38mm Lectron for my WR300, first gen, 3-1XL rod is 49mm.

I'll be setting to match that, testing it out (without making any further adjustments) and switching over to focus on the ignition situation.

The workshop manual for the 2011 has a procedure to test the stator, however, it does not seem correct to me.

Alternator check

Disconnect the regulator from the wiring. rev the engine up to about 3000 r.p.m. and measure no-load voltage across the BROWN wire and the ground using a VAC voltmeter with a scale at least up to 50V.

The voltmeter will show a voltage readout 35,5 V.
If there is no readout or voltage is mardely unbalanced, the stator is faulty.; in this event, check insulation across tested wise and grounf using an ohmmeter. Insulation must be total, i.e. resistance must be infinite.

Direct from the manual, spelling and typos carried over to match.

Looking at the wiring diagram, this seems wrong. Attached is a smaller version of the diagram (with the yellow A/C wire powered accessories removed). Where I drew the red line would be the break at removing the regulator. If that is circuit is broken, then there is no longer A/C power going to the CDI/Coil. How would the engine run at 3,000 RPM, without having A/C power to charge the coil and produce spark? On other bikes this would work as typically I don't see the coil being powered from the regulator, making the regulator basically an unnecessary part. I'm hesitant to bypass it though. As the reports of the CDI burning out on Ducati ignition bikes being started with a headlight on, would put the likely culprit as a failure at the regulator rather than the CDI itself, basically, the regulator failure causing the damage to the CDI.



With this tie-in, it could be the regulator itself is bad. So, if I can determine the stator itself is good, then tomorrow I can pull what I need to on my dad's "donor" bike (he's gone for the week anyway, so don't say anything). If I can't confirm which part is bad, I don't think I have much option than to go back to the PVL and try to get it sorted. No information is provided for testing the regulator or CDI individually, so I'm not sure how successful I'll be in determining that, but I'm thinking I'll be taking a meter to my dad's bike and recording everything I can think to measure, to compare against my components.


Unfortunately, I can only get away with firing up my bike so late in my neighborhood and I usually don't make it home from work until about 6:30. So, after about 9PM, I'll have to switch over to replacing wheel and linkage bearings. It's going to be a long week. I think I feel a sick day coming up. Although I'm already taking off Monday to drive back from TX.

 

[msmith345]

WTF? I ditched work early and came home to work on the bike with a little more day light. Set the Lectron back to 49mm. Started right up, tiny tweak of the idle screw and bike is running perfect. All the snap is back and no more killing itself after 30 seconds idling. Let it idle for a good a minutes. Adjusted the idle screw just a tad more. And then took a ride to see if my hopes were raised too high again. Nope, all the snap is there, pulls clean idle on up. I owe Kelly a giant beer. I still don't know how I got that far off. With as much turning as I had to do, I'd bet I was all the way out to 54mm.

Electrics might be OK after all. I was losing my mind.

Now at least I can move on to the rest, having reasonable confidence my bike is going to run well enough to get me through the enduro.

Still think there is something funky in the manual on testing the stator. I didn't try to pull it since it's running good now. Don't want to jinx anything.

 

[ks9mm]

Thanks for the fun read man! hopefully you will not jinx it now!

 

[msmith345]

I knocked on wood, threw salt over my shoulder and did ever superstitious ritual I could think of after posting that. We'll see this weekend. Still wishing I had a chance to actually test it before then, but it's not in the cards. The trip out to the parking lot of the closest riding area in a snow and rain mix yesterday morning was my last chance to do that.

Front wheel bearings and brake pads in, onto the linkage. And you better believe I'm going to be riding this through the neighborhood every chance I get this week to make sure it's all square.

 

[msmith345]

Ok, got everything (almost) finished up last night about 1 am. Only to realize that the chain adjusters won't go in far enough/chain is too short, for the 14/48 setup.

I pulled the chain adjuster bolt completely out on the left side, and it was all kinds of torn up. It seems it was hitting something inside the swing arm if I tried to go in further than the 6th tick mark fro the back. That left about 1/4" threads between the lock nut and the bolt head.

So, as I see it I have 2 options. 1) buy a new chain at Cycle Gear over lunch, or 2) pick up 2 new m8 bolts over lunch for use as shorter replacement chain tensioner bolts. I'm not looking forward to having to change from the 10mm head, but I don't think I'd be able to fine any like that at the hardware store. Might have to go to allen head socket bolts for clearance.

I wouldn't be able to get a 13 tooth 360 front sprocket today, so that's not an option right now. But I will probably try to do that before next weekend.

Anyone seen this issue with the left chain adjuster? The right one does not hit anything. I can't drill it out, and I can not fit a tap in to clean the threads out.




And by the way, don't be an idiot like me. The triangle part of the linkage has an aluminum stop cast into the middle. You can't pull both bearings through, they have to be knocked out. I only spent a couple hours and a bottle of propane figuring that one out. KTMs for too long, the last linkage I replaced bearings in was a KX65 and those pulled though IIRC. But a 1/16" tungsten carbide cutter for the dremal tool will make short work of the race and give you enough precision to not cut into the aluminum. Making removal of the first on each side easier, then using the installer and a socket to pull the other side through.

 

[Eaglefreek]

And by the way, don't be an idiot like me. The triangle part of the linkage has an aluminum stop cast into the middle. You can't pull both bearings through, they have to be knocked out. I only spent a couple hours and a bottle of propane figuring that one out. KTMs for too long, the last linkage I replaced bearings in was a KX65 and those pulled though IIRC. But a 1/16" tungsten carbide cutter for the dremal tool will make short work of the race and give you enough precision to not cut into the aluminum. Making removal of the first on each side easier, then using the installer and a socket to pull the other side through.

That sucks. That's been talked about a few times on the forum and as suggested, a blind bearing puller works perfect for removing those bearings. I used the "loan a tool" program at Autozone to get one.

 

[msmith345]

I've got a blind bearing puller, but it seemed to be between two sizes. And no way to really hold the piece to use the slide hammer. I really didn't want to clamp it in my vice as it's got some serious shark teeth on it.

Bearing puller is a worth while investment. It makes wheel bearing replacement a quick job.

 

[Eaglefreek]

What others have done, is put the puller part into the bearing and it catches the inner lip. Then use a hydraulic press to press it out from the other side. I didn't have a press, so I set the linkage on a large pvc pipe fitting and pounded it out from the other side with a copper dowel. It didn't take much force. http://www.cafehusky.com/threads/linkage-bearings.23035/#post-206640

 

[msmith345]

Well, Concho is in the books. Bike was thoroughly tested and abused.

Report is in.
1. 6 speed was great on the bike. I want to go to 13/48 gearing to see if it improves the lack of grunt on the 250. The shift mechanism is a bit finicky. I had a lot of neutrals when I was clicking from 1st to 2nd.
2. The 250 is a harescramble bike, not an enduro bike. I can not explain how disappointed I was in the lack of grunt-ability of the 250. In faster sections it was awesome, but it did not hold a candle in regards to tractable power that the 300 or 360 have. Traction was limited in the dusty, rocky hardpack and the 250 didn't help matters. If you make the terrain less technical, traction better, and speeds higher, the 250 would be a heck of a ticket. It feels like you can really crank it open and with the 6 speed, it's really going to move fast in the transfers.
3. With the terminator clutch cable, the clutch pull seemed more exhausting than it ever was on either the 300 or 360. This very well could be my lack of riding in the last 5 months.


I'm not sure if there's a way to make the 250 work how I want it to, short of going back to the 300. I may look into a FWW, or I really don't want to, but a rekluse might suit the setup as well.


Good thing is I know exactly what I want now:
* 2010-2014 WR250/300 frame.
* 360 engine with a balanced crank for less vibes.
* professionally done suspension
* solid mount triple clamp with stabilizer
* Lectron 38 (because I wouldn't run without one now)
* Mechanically assisted clutch pull. I've got some ideas I thought about on my 10 hour drive each way. And once I move I'm getting a mini-lathe and mill to build out a number of prototypes. I've got a good 4-5 parts I noted down that would greatly improve was currently available.
* Take that entire package and drop 10-15 lbs from it.


So, I guess once I get moved, I'm going to have some things to think about. I was planning on my next project being the 390 ACC I just picked up, but I might have to put that on the back burner and come up with a better big bore.

 

[Kyle Tarry]

Following your exploits with interest.

What is the current state of your suspension?

Would you be interested in brainstorming some of your ideas for the clutch? I have the same complaint, and I have had some ideas and would love to hear what you've got. I have made a couple small changes to mine, and they helped but it wasn't the solution. I've considered going to a hydro clutch, but before I go that route I wonder if there is a cheaper/simpler option. My clutch doesn't bother me on a trail ride, but in a technical tight enduro, after riding all day, it's not good. A rekluse would "fix" that problem, but it comes with other downsides and isn't cheap.