Dtr 125 1997 Rebuild/Restoration
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@Mr-Shadi Here's a link to a YZ-style rear mudguard designed to fit the DTR:
https://www.bikerpartshop.com/en/home/24-rear-fender-mudguard-cross-for-yamaha-dtr-125-200.html
In fact you can replace all the plastics from here pretty cheaply and they fit well. I'd sooner do that than paint your originals as painting itself costs money and plastics are very difficult to do well, they flex leading to the paint cracking quite quickly:
https://www.bikerpartshop.com/en/17-dtr
Also this guy on eBay does some very good quality graphics:
https://www.ebay.co.uk/usr/hazard_graphics?_trksid=p4429486.m3561.l2559
There's not really anything wrong with the stock DTR front end structurally; the springs are just too soft for off-roading. 41mm stanchions are only like 2mm smaller than the 200kg+ GSX-R1100 when the DTR was released in 1988. You can make major improvements to the DTR suspension by running XT600 3AJ fork springs (same size but 20% stiffer) and 15W oil at the stock level, a relatively cheap fix which means you can spend the money you have left over on an adjustable YSS shock, again a major upgrade for the bike (although I have heard of people fitting an XT600E spring to the rear shock to stiffen that up as well). Doing this made my '98 DTRe jump and resist bottoming a lot better than the 2020 KTM 250EXC I also owned at the time. Also get a grease gun (£25 on eBay) so you can keep lubing up the swingarm/linkage bearings after every wash/offroad riding session.
Some people do the USD front end swap but the trouble with this is, most of them you get down the breakers have had a hard life on MX bikes so you really need 3-4 sets exactly the same make/model/year to ensure you have spares (a lot of people "fit YZ bits" not realising MX bikes are updated EVERY year). Fun fact: when the 1st-generation USD forks appeared in 1989, Kawasaki USA (i.e 7-times US national MX/SX champion Jeff Ward) tested them in Japan and weren't impressed; they opted for the 46mm conventional forks to be fitted to all '89 KXs sold in the US which performed better than the USDs by all accounts. Even today in vintage MX circles, an '89 KX250/500 imported from the US is very sought after.
Other off-road preparation: Get a cable oiler from Yambits and lube the cables with Comma Spray Grease. Also Yambits air filter elements are very good quality, fit well and are half the price of OEM so it's worth getting a few of these and cleaning oiling them in rotation so it's easy to just throw on a fresh one after every wash. Seal the carb-to-airbox rubber with petrol- and oil-resistant glue as this is downstream of the filter and your engine can suck dirt if this isn't done:
https://www.repairingproducts.co.uk/product/seal-all-gas-oil-resistant-adhesive/
Use more Seal-All to replace the 5mm air filter foam on the back of the element holder where it slides into the airbox (5mm air filter foam is cheap on eBay).
Run a 100/80W halogen bulb in the stock headlight; Yamaha cheaped out and fitted a 45/40W candle from new but the actual light is the same unit as 900cc+ Yamaha superbikes of the day and the DTR's AC lighting means high wattage bulbs won't flatten the battery. This lights up the trails like a rally car.
Make your own powervalve cables from MTB gear cables so you can re-lube them in situ; these cost less than buying a genuine set, last longer and protect your valuable YPVS servo:
https://dt125r.co.uk/topic/2971/home-made-quick-lube-ypvs-powervalve-cables
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@HOTSHOT-III Thank you lad. I saw a video on yt about the tz style plastic but the link didnt work and google gave me nothing. Also i ride it as a hobby and mostly smaller tracks bc the bike struggles on bigger tracks, i live in Estonia. And about the suspention i was thinking on the rear shock you gave, but the front. I was thinking on putting heavier oil like w20 and spacers on the springs. As i said my budget isnt that big and most of it is going in to the restoration so i am going to be left with probably 300 to 200 euro for straight upgrades and new parts. I am gonna respond to this in more detail after Christmas. Right now im typing this on my phone and im a bit of a hurry with the Holliday activities.
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I ended up fitting WR450F forks on my DT. The forks and yokes cost probably around £200 and then it was just the case of turning up a spacer on the lathe and adding a brake backet. The result was fully adjustable front suspension, hard for the road and soft for the dirt trails
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Putting washers or spacers in the forks doesn’t make them harder. It just pre-compresses the springs. Heavier oil will change the dampening, but also won’t make the suspension harder…
I spent £100 on (progressive) aftermarket springs. They’ve changed the whole feel of the bike for the better. I’m not doing air with it though
It’s aimed at road use mainly, a lot more stable at speed… -
@SpookDog i just got new front fork from my uncle. He had a yamaha dt 125 back in the day, but i dont know witch year. il send a pic of them soon. The fork has adjustability settings on top and also bottom. They need a oil change but should be good for replacement front forks.
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Well, that's no excuse. Look at what @SpookDog has achieved out in the exposed elements. In the brevity of dry spells he's out there smashing a restoration!
Anything is possible.
That said, unless it really needs it, you'd probably get away with just waiting.
Always Originate, Never Pirate!
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Quickly?!
…I’m sorry but I don’t remember where you are in the world, Eastern Europe?
Metal does strange things at those temperatures. You can shatter it like glass if you’re not careful. You can absolutely guarantee that a spanner will slip and you’ll skin your knuckles!… -
Hello again.
Ive returned and i will start my build waay to late in to the summer.
Ive ordered new parts and id like to know yalls opinions
The parts:
Full Athena exhaust,
piston,
turn signals,
Plastics,
Pwk 36 carburetor,
Athena gaskets,
Bearings and bushings,
And a little paint.Im planning to go full black on the plastics and put dark blue decals on them, also im going to paint the frame yamaha 403 dark blue.
Ive already upgraded my front suspention with dt 125 1980-1990 sumting motocross springs, heavier oil 15w, and put the stock spacer in my right fork. For the rear ive maxed out the shock and it rides lika dream even without the new parts yet.
The engine is in pretty good condition, all the gears are good but ive noticed that some bearings need to be replaced. I am very suprised that my crank is still good and not rattling beacuse ive used the bike for enduro/motocross/road usage. But my 3mb00 cylinder has a mirror finish and with my old piston has 75 psi but it still ripps and keeps up with a 2017 ktm sx 125 on full gas. Im sending the cylinder to my local shop to get it honed, then il run it with my old puston till the new parts arrive.
On the electrical side, everything is in meh condition. I need to rewire some parts and make some adjustments so i can put on my new turn signals. The biggest problem tha i have is that my derestrictor switch dosent work on the first try, i need to switch it for 30 seconds or so that it derestricts it and i have been thinking of putting somekind of a toggelable repeater on it so i dont have to mess with it, but i havent decided.
About the frame. It has some rust and dabage but mostly its all good, as a said before im thinking of spraying it with yamaha 403 dark blue paint, other than that im going to replace my swingarm bushings tomorrow, beacuse they are shot and rusted as hell.
For the drivetrain i bought a 15/51 sprokets so i can cruise at 90km/h in about 6000rpm and the top speed should be around 135km/h according to gearingcommander website.
Lastly i would like to ask, is there a way that i could increase my revs to about 11k rpm? Right now it maxxes at like 9.5k and dosent sound the best.
All the feedback is greatly appreciated.
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@Calum i am thinking on ignitech programmable cdi. Its about 200 euro and one of my friends used that. Is zeeltronic a little better than that? Comparably they to pretty much the same thing and can be programmed similarly, but zeeltronic is just more expensive.
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