Stevie’s French '98, Mid-90's WR/YZ/DT (An idiotproof guide to building your own DTR)
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@Stevie-Wonder With the engine removed from the frame, now would be an opportune moment to test the fitting of your DT200WR swingarm. Sounds counter-intuitive I know, but assuming the swingarm pivot bosses are the same width/distance apart as the stock steel arm (meaning it will fit into the chassis), it's the engine boss which dictates it's (and in turn the rear sprocket/wheel) position in the bike. Sprocket alignment is the biggest enemy here; you won't notice front/rear wheel alignment being a few mm out as once you factor in tyres, rims etc. (MOT allows 4mm lateral rim runout) most bikes on the road aren't perfect anyway.
Here's an explanation how to do the swingarm side clearance with pics from the Yamaha manual. Don't forget you'll need to do this again after splitting and reassembling the crankcases as this process might alter the engine boss width:
https://dt125r.co.uk/post/29135
It's actually possible to do this without going near the chassis if you have the engine out; I went through the process using a 3ET swingarm and a spare set of crankcases to do a workbench mock-up to assess sprocket alignment. 3ET swingarm, spindle, drive side spacer and rear caliper mount (it's thinner due to the fatter ends of the alloy arm) and stock DT125R hub produced almost perfect sprocket alignment according to my 600mm straight edge. I might need to play around with this slightly to get it perfect; there was a 3mm thick M20 washer between the caliper mount and arm when this pic was taken and the sprockets look about 1mm out.
Good shout going back to an 18" rim. If you can, go back to your stock 18" DTR rear wheel as well because stock rear wheel with good sprocket alignment = wheel alignment (or at least it places your stock rear wheel where it should be) which will keep things simple for now. Also 19" rear wheels on MX bikes were largely an attempt to reduce the rear wheel's weight which reduces unsprung weight/inertia to improve acceleration and suspension responsiveness on the track; most Enduro bikes run 18" because the flabbier tyre sidewall is more forgiving and offers better puncture resistance against rocks, roots, Ferguson tractor parts in the corner of farmers' fields etc.
https://www.thumpertalk.com/forums/topic/213621-18-vs-19-wheels/
I can't comment on the DT200WR arm as the chassis is different from the DT125R as well meaning you might need the entire rear suspension assembly to make it work (the DT200WR shared a much beefier relay arm and linkage with the WR200 IIRC). And compared to the 125 steel arm I'd be looking at overall length as well as the distance between the pivot and where the linkage attaches to try and get an idea whether the leverage ratio will change noticeably.
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@HOTSHOT-III said in Stevie’s French '98, Mid-90's WR/YZ/DT (An idiotproof guide to building your own DTR):
@Stevie-Wonder With the engine removed from the frame, now would be an opportune moment to test the fitting of your DT200WR swingarm. Sounds counter-intuitive I know, but assuming the swingarm pivot bosses are the same width/distance apart as the stock steel arm (meaning it will fit into the chassis), it's the engine boss which dictates it's (and in turn the rear sprocket/wheel) position in the bike. Sprocket alignment is the biggest enemy here; you won't notice front/rear wheel alignment being a few mm out as once you factor in tyres, rims etc. (MOT allows 4mm lateral rim runout) most bikes on the road aren't perfect anyway.
Here's an explanation how to do the swingarm side clearance with pics from the Yamaha manual. Don't forget you'll need to do this again after splitting and reassembling the crankcases as this process might alter the engine boss width:
https://dt125r.co.uk/post/29135
It's actually possible to do this without going near the chassis if you have the engine out; I went through the process using a 3ET swingarm and a spare set of crankcases to do a workbench mock-up to assess sprocket alignment. 3ET swingarm, spindle, drive side spacer and rear caliper mount (it's thinner due to the fatter ends of the alloy arm) and stock DT125R hub produced almost perfect sprocket alignment according to my 600mm straight edge. I might need to play around with this slightly to get it perfect; there was a 3mm thick M20 washer between the caliper mount and arm when this pic was taken and the sprockets look about 1mm out.
Good shout going back to an 18" rim. If you can, go back to your stock 18" DTR rear wheel as well because stock rear wheel with good sprocket alignment = wheel alignment (or at least it places your stock rear wheel where it should be) which will keep things simple for now. Also 19" rear wheels on MX bikes were largely an attempt to reduce the rear wheel's weight which reduces unsprung weight/inertia to improve acceleration and suspension responsiveness on the track; most Enduro bikes run 18" because the flabbier tyre sidewall is more forgiving and offers better puncture resistance against rocks, roots, Ferguson tractor parts in the corner of farmers' fields etc.
https://www.thumpertalk.com/forums/topic/213621-18-vs-19-wheels/
I can't comment on the DT200WR arm as the chassis is different from the DT125R as well meaning you might need the entire rear suspension assembly to make it work (the DT200WR shared a much beefier relay arm and linkage with the WR200 IIRC). And compared to the 125 steel arm I'd be looking at overall length as well as the distance between the pivot and where the linkage attaches to try and get an idea whether the leverage ratio will change noticeably.
Thank you for that @HOTSHOT-III thats really helpful. The swinger still needs painting, which I’ll get round to eventually none the less I’ll be doing what you said.
My 19” rear is just a YZ rim laces to DTR hub so in theory the alignment should be the same. -
I’ve since split the cases, I don’t have photos but the top end was pristine. The head had no plinking/det marks, crosshatching on the bore still, perfect even burn pattern along the piston crown and a beautiful bronze/brown colour. No play in the crank either.
My suspicions were right and both seals had in fact given up. A quick call to PJME for a round of oem seals, power valve rebuild kit, Yamaha seals and some koyo crank bearings for good measure and we’re sorted.
I also did some tinkering today and found out what’s wrong with my clocks as I was having issues with using the stock ones with my USD forks.
-The Speedo side of the clocks fine, however when I hooked up I didn’t get reading so the speedo drive is possibly faulty. Plus to make matters worse speedo drive is to opposite side of the clocks meaning you can’t route the cable properly.-I found out the rev side of my clocks has seized somehow which is why my bike snapped two cables.
(If anyone has any experience with taking the clocks apart that’d be great, are they complicated/fiddly?) -
Standard clocks? You have to separate the base with a Stanley knife. Then stick it back together with mastic/sealant…
I’d try wd40 and try to get it moving with a screwdriver or such. The bit that spins has a magnet inside the unit that sits inside a kinda steel ‘bell’ that connects to the needle. The spinning magnet moves the ‘bell’ which has a very delicate return spring…
It’s fiddly but doable. If the gauge is fubar you’ve got nothing to loose… -
Cheers man I’ll give that a try
Engines back together now, took an afternoon to do between me and Stacey of VJMC Suffolk division, the crank bearings and seals come out no trouble and it was fun educational experience. They’re surprisingly simple and light.
Still learning about the gearbox aspect. That’s gonna take a couple more goes before I get.I polished the piston crown, rebuilt the powervalve and through a set of koyo main bearings and used OEM everything else.
Unfortunately I forgot to order a Reed gasket so we’ve had to put it on hold until that comes back, then we can see if she runs.
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@Stevie-Wonder
More hands on you get, the more confidence you gain. Good to hear you’re still around
You been riding that FZR, wasn’t it? Revvy 4/ fun!…. -
Yes my FZS600, a great bike with plenty of power. Very Rev happy, very reliable too. I’d definitely own one again. Unfortunately I had to sell it. My only complaint isn’t really so much a complaint but more personal preference and that’s that it felt like riding a two stroke, the power was very linear yet flat at low revs but increased more and more with the revs. It makes for a lot of fun but personally if I wanted that feeling I’d just experience the real deal by riding a two stroke. If I’m riding four stroke I like bottom end and not having to constantly be on revving the tits of it. It gets annoying after a while, that is unless it’s a two stroke.
Update with the bike, I’ve sourced some parts for the DTR thanks to a certain someone (forget their @). I’m getting rid of the 200r headlight, making a second rear plate holder and at some point I might buy some replica OEM indicators. The 19” rear will eventually go but I’m not replacing it with anything other than an excel 18” so that’ll take time and $$$. From the parts I sourced was a headlight frame to put the original back on, quite looking forward to putting the original back on to be honest!
I do need to somehow sort out a mount for it. I also replaced the rear mud flap as my one got eaten by a whopping great big knobbly that I put on my bike when I first got it. 140/80-18’s aren’t for your bike is what I’d tell myself if I could
.So far so good with everything really, since being rebuilt I’ve only rid her around a couple times, she’s yet to go on any proper outings though.
On my list of jobs to do was to change the pads as the right side of my EBC pad had literally just fallen off. What was meant to be a quick job turned into a bit of a nightmare though as the calliper wouldn’t come away from the hanger. Many hits and a lot of heat made absolutely no difference at all. When it finally did budge it was just the thread of the pin coming loose
I’ve since disconnected the calliper from the hose and left it to soak in methylated spirit as the Aussie’s on fb said that remedied their issue with the calliper fusing/seizing to the pin to their 200r’s.
I’ve been told it’s a common problem, if any one has any advice for this then let me know.Id noticed the seals of the piston protruding out too, so whilst I am tempted to push the piston in give it all a thorough clean and then Chuck it back together so it’s sorted, I know it’s only going to be a temporary fix and it’ll need to be done one day.
Plus knowing that my callipers seized to the hangar bucks the shit out of me because everything else on my bike has been perfect,
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Uuuhhmmm, two strokes aren't linear power. I think you've misphrased that.
A lot of road going four strokes I've ridden are gutless and you have to wring their necks to actually make them fast. I don't see that as being akin to a two stroke.
ZX6R
Where as an RD350LC, or two stroke will have a much more erratic explosive powerband.
Bear in mind on the RD, you're talking about something which makes DTR power just above idle. So they are very rideable, but the real fun/power is up at those higher RPMs.
You really need to be up there (750cc+) on four strokes for them to actually be fast IMO.
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A lot of road going four strokes I've ridden are gutless and you have to wring their necks to actually make them fast. I don't see that as being akin to a two stroke.
That’s exactly what I mean, I’m not talking about the literal powerband but the way the bike feels and is ridden. That revvy in-line four akin to the DT is begging to have its necks wrung because you literally double the amount of power high up in the revs and like said that’s how you make them fast
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@Stevie-Wonder Yeah, I see what you're saying. With a bigger 4 stroke it's not like that so much. I haven't yet ridden a super bike however.
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I had an old Suzuki gn/dr 400 single cylinder mongrel that I put a sidecar on so I could ride it on L plates. It was like riding a tractor it was so torque’y. Uphill or down, pull away whatever gear, it just loved to pull
Gotta love torque!I lost a lot of brake power to having a worn slide pin. The calliper just kinda tilted sideways for a big part on the levers throw. I was going to drill out the calliper (the hole was oval-ed) and put an oversized pin in, but couldn’t find one.
Failing that put a brass sleeve in it and a standard size new one, but couldn’t find one! Got a titanium one that turned out to be too small diameter. Gave up and just stripped it and replaced the rubbers and seals. Grease the pin!Apart from major heat I’d soak it in vinegar or washing soda, or even caustic soda to try and release it. Also, if it’s that corroded I’d replace the piston with a stainless or titanium one…
Good luck bud, nice to know you’re still about…
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@Calum when I rode a CBR900rr fire blade it still produces that same style of power but was no where near as revvy as the fazer.
The fazer wanted to be ridden past 8k everywhere, by all means you could ride it under but it just didn’t feel like you was using it properly
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Good looking thing! Love the decals in front.
My bike got stolen and smashed to pieces and I was sick of the sight of it, hence why it went and got modified.
Both my previous DT125's were stolen, smashed up, and found in a ditch. First in 1991, second in 1999. What it is with DT's and sadistic thieves?
The second one had done a thorough job, there were wooden sticks protruding from holes in the expansion chamber and headlight.
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@Hark_Ptooie said in Stevie’s French '98, Mid-90's WR/YZ/DT (An idiotproof guide to building your own DTR):
Good looking thing! Love the decals in front.
My bike got stolen and smashed to pieces and I was sick of the sight of it, hence why it went and got modified.
Both my previous DT125's were stolen, smashed up, and found in a ditch. First in 1991, second in 1999. What it is with DT's and sadistic thieves?
The second one had done a thorough job, there were wooden sticks protruding from holes in the expansion chamber and headlight.
@Hark_Ptooie I think it's jealousy. When you're 17-18 yrs old and rock up on a flash 125, it really gets people's backs up, specially if they're the kinds of teenagers who aren't capable of anything more than sitting in a bus shelter, drinking two litres of cider and endlessly complaining "there's nothing to do round here".
When I got my 1st DTR at 17 it changed my life, we lived somewhere pretty remote by UK standards but suddenly I was able to ride out 7 or 8 miles to the nearest town and see some mates. So I unwittingly came in for rather a lot of this because I had a nice DTR, plus the fact I was faced with the petty-minded attitude of people who realised I didn't grow up on their street, go to the same school as them etc. This included:
My bike being vandalised several times when parking it in the middle of town.
An endless supply of bozos flicking the kill switch to "off" when I wasn't looking.
On one occasion I parked the bike outside a pub full of "local people" and someone pulled the 2T oil feed pipe off the reed block which resulted in the engine seizing solid at nearly 70mph. AC lighting + seizure = the lights go out when the rear wheel locks in pitch darkness. I saved it with the clutch but this was a terrifying experience and extremely spiteful, whoever did that knew what they were doing with two-strokes and fully intended to cause harm. I never found out who did it.
I went to school in the 80s where we had it drummed into us that we were very lucky to live in the free world. The Berlin Wall came down when I was 15 and I'll never forget watching the people streaming across the border on the news, it was the 1st political event I ever paid attention to. Looking around at all the beautiful consumer products we're able to own in industrialised western countries, it's a great shame that jealousy, cowardice and fragile egos conspire to mean one has to be careful. If you read the chapter in Animal Farm where one of the younger pigs comes up with some new ideas to run the farm more efficiently, and the senior pig urinates all over them before storming off, that is basically the mindset you're coming up against with such people. In the USSR they could send you off to the gulag but in a free society, they have to be content with fucking up something owned and enjoyed by you.
https://www.youtube.com/watch?v=znb_X48WXUg&t=3s
Please don't consider this a negative post. Individualism is a lonely and difficult journey but 100% worth it.
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Yeah, I suppose. I went back to uni when I was 30 and had a CBR929RR. The rest were all like 19 year old and didn't even meet my gaze, least of all talked to me. And one day I found a hole in the saddle.
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@Hark_Ptooie oohh lovely bike that!
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It was nice, but after four years I developed chronic neck and wrist problems from the seating position. These days I ache if I so much as look at a sportsbike.
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New set of clocks has arrived
I’ve got the speedo drive working with the WR450 / 250 setup
All that’s left to do is make a new frame / bracket for the clocks then hook them up.
A small victory knowing I’ve managed to do the USD swap and get the original clocks working. I’m very pleased with this.
I’m putting the original headlight back on, I just need to hook up and attached to the headlight frame and write down what have gone missing in the time it’s been off and order on fowlers.
I’ve also stuck the original front fender on.
I’ve noticed some leaking from underneath at the bottom the engine around the casing gasket and water pump (right side). Not good but it’s been sitting since being rebuilt a year ago.
Lots lots more to be done before she’s properly done but I’m back in business and getting my arse in gear again. Peace. Hope all of you are doing well and always thank you for your help and being a part of this journey
Ride on.
