Motorcycle Alabama

Open House => Tech Talk => Topic started by: Gam on July 01, 2021, 05:06:36 PM

Title: 1973 Yamaha DT3 restoration
Post by: Gam on July 01, 2021, 05:06:36 PM
I bought this bike back in 2017 for $500.00. It sat at a buddie's house in Colorado until a couple of months ago, I finally had it shipped to me. There is pic still on this page where I was asking about the tank dent back in 2017.  Looks to be in pretty good shape, eh? You can't see that big honking spigot style Chinese carb mounted with pieces of car radiator hose, or the all the other things that look OK but are completely worn out. I've learned one thing, you work on it 15 minutes and then spend  hours on ebay and other places looking for parts. Finally the super rare part shows up, there are tons of bidders, you panic and just click "buy it now'.  The next day there several of the rare part for sale in better shape and at a cheaper price.
(https://gamike.smugmug.com/Yamaha-restoration/i-QTT7CQ6/A)

First panic purchase was this carb all the way from Australia (yes there is now one available in the US in better shape). For some reason the carbs on these bikes were painted black. Pretty ugly, but it did have real Australian outback dirt on it.

(https://photos.smugmug.com/Yamaha-restoration/i-QTT7CQ6/0/acd0f2c9/M/tank-M.jpg)

Looks like somebody got a little frustrated trying to get the O ring out.  Dab of JB Weld ought cover that.
(https://photos.smugmug.com/Yamaha-restoration/i-WZfMwQc/0/de5b48c7/L/CARB%20BROKEN%20FLANGE%20%281%20of%201%29-L.jpg)

pretty much got the paint off, I was afraid to just start dunking it in Chem Dip or whatever, kept thinking about having to fish paint flakes out of those tiny holes. I have a rebuild kit, but waiting for parts to come in that you don't find in the rebuild kit. I plan on repainting it black.
(https://photos.smugmug.com/Yamaha-restoration/i-gJhmCK7/0/64f0147a/L/stripped%20%281%20of%201%29-L.jpg)
Title: Re: 1973 Yamaha DT3 restoration
Post by: Gam on July 05, 2021, 12:25:31 PM
I got the air box stripped and painted and the battery box and tool box stripped. My spray paint fu is not too great, drips and blow spots from holding too close, I never wash bikes, much less paint them.
(https://photos.smugmug.com/Yamaha-restoration/i-jCbQ7LJ/0/e659b1b5/L/airbox%20primed%20%281%20of%201%29-L.jpg)
(https://photos.smugmug.com/Yamaha-restoration/i-HJZBpfN/0/7c1c8d27/L/painted%20airbox%20%281%20of%201%29-L.jpg)

I had a 1971 DT250 back in the day, this is only pic and it is frame from 8mm video, my main bike was a husky then, and we used my DT250 as a sacrificial bike in one of those all day partner events. Couple of gottchas on this bike.
(https://photos.smugmug.com/Yamaha-restoration/i-RrvCQXD/0/286eab6f/M/me_DxO-M.jpg)

This gear shaft detent is one. The bolt is on the bottom of the case, as is the oil drain. Oil will drain out of the hole for this thing, and if you don't realize that this is not the oil drain, then you are likely to lose that spring and little slug in the oil. Then you wonder why your bike jumps out of gear. New spring found on ebay, the old one was broken into 3 pieces.
(https://photos.smugmug.com/Yamaha-restoration/i-cNWLxTr/0/37d3125a/L/detention%20spring%20%281%20of%201%29-L.jpg)

I found this note in the tool box. Pretty much all you need to know.  I bet the lights still don't work.
(https://photos.smugmug.com/Yamaha-restoration/i-h9QLdgQ/0/274a67c1/X2/note%20%281%20of%201%29-X2.jpg)

Title: Re: 1973 Yamaha DT3 restoration
Post by: Gam on July 11, 2021, 04:05:04 PM
I've put off checking for spark, I guess it's time.
(https://photos.smugmug.com/Yamaha-restoration/i-LvwLQZw/0/683a31da/XL/completed%20air%20%20%281%20of%201%29-XL.jpg)
Title: Re: 1973 Yamaha DT3 restoration
Post by: Gam on July 18, 2021, 11:03:25 AM
Finally a little luck, except for a dead spider in there, the reed valves were in great shape, not a bit of light coming through.
(https://photos.smugmug.com/Yamaha-restoration/i-25xw4ZG/0/fc48b71c/X2/reed%20valves%20%281%20of%201%29-X2.jpg)
Title: Re: 1973 Yamaha DT3 restoration
Post by: LawnmowerRG on July 20, 2021, 03:29:55 PM
Looking nice man.
Title: Re: 1973 Yamaha DT3 restoration
Post by: 2smoke on July 24, 2021, 10:05:50 AM
I certainly remember those, looks good  :)  I have found several odds and ends including OEM for a 72 Suzuki 185 on bikebandit
Title: Re: 1973 Yamaha DT3 restoration
Post by: Gam on October 17, 2021, 01:45:37 PM
i started this thread so I would stay motivated to keep working on this. I've been working on it, but not posting anything. Looking pretty sweet, huh? ;D I don't think Barber would be particularly interested in it. Here it is in my spacious shop ( 12 by 10 shed, no lighting, shared with a KLX).
(https://photos.smugmug.com/Yamaha-restoration/i-rBbbZ7g/0/ec711b33/X3/parts%20in%20shed%20%281%20of%201%29-X3.jpg)

The cylinder has been bored to the first oversize, it took a while to find a first oversize piston. A guy who does this stuff is making me a new wiring harness and attaching it to the ignition and dimmer switch. All the wires had been snipped off except the ones to make it crank without a switch. Not complicated wiring, but it would have taken a while, plus there is a  bunch of soldering to the switches, the tank is out being de-dented and painted along with all the other  color part.  Decided against a rattle can job or one of those purple Harbor Freight paint guns. These boxes are full of endless bits and pieces I had to find and order, anything rubber is petrified or turns to dust in your hands. There was a good bit of bailing wire, square nuts, and other innovations holding it together.  Going to powder coat the frame. Still have to think about the rear shocks,  and pressure testing when the jug is back on, I will be surprised if the seals are still holding.
(https://photos.smugmug.com/Yamaha-restoration/i-n3fW69n/0/d46e3b3a/X3/new%20parts%20%281%20of%201%29-X3.jpg)
Title: Re: 1973 Yamaha DT3 restoration
Post by: Gam on December 13, 2021, 04:29:06 PM
All the green stuff is painted, looks like scratches on the tank, just reflections. Got to find somebody to powder coat the frame, and I will be ready to start putting this thing back together.

(https://photos.smugmug.com/Yamaha-restoration/i-KFxDg68/0/b1dfe25e/X3/painted%20parts%20%281%20of%201%29-X3.jpg)
Title: Re: 1973 Yamaha DT3 restoration
Post by: Gam on April 04, 2022, 05:27:55 PM
Frame is powder coated, hope I can remember how this thing goes back together.  Motorcycle parts and fishing rods everywhere, never guess I live alone. 

(https://photos.smugmug.com/Yamaha-restoration/i-TKr6c6P/0/20e742a5/X2/frame%20%281%20of%201%29-X2.jpg)
Title: Re: 1973 Yamaha DT3 restoration
Post by: TFancher on May 12, 2022, 07:56:58 PM
My dad bought me a 1973 DT100 just like this when I was 12. I found this one a little while back and bought it. I cheated though. Mine was in good condition when I got it! Brings back a lot of good memories. 
(https://uploads.tapatalk-cdn.com/20220513/10ca5657fcc28b1b8a4ceb75b3a0847e.jpg)


Sent from my iPhone using Tapatalk