Yamaha 250 DT1-C

1970 Yamaha 250 DT1-C

I had been wanting to restore my old Yamaha for a long time but never had a way to get it from the farm in Wisconsin to Georgia to work on it. In 2013 we took the new 14' cargo trailer on the Wisconsin trip and only had 2 dirt bikes in it so there was room for a third bike on the return trip. That was in October 2013.

Bike History

I couldn't remember exactly when I got the bike but fortunately my brother (Bob) could. Bob bought the bike from my Uncle Fritz's friend, Pete, in late 1973 for a whopping $400. After hauling it home from Milwaukee, he took his driver's test on it (it was street legal at the time) and then rode it to high school as much as he could.

In the spring of 1976, he bought Uncle Fritz's 1969 DT1-B with a gold-colored tank and raced it for a season. I bought the red-tanked DT1-C from Bob so he could buy the gold-tanked DT1-B. While racing, Bob kept getting beat by a guy on a Yamaha 400 so in late 1977 Bob sold the gold DT1-B and bought a Yamaha 400 with a mono-shock rear suspension. Mono-shock technology was brand new back then. It was a marvel to behold (and ride) after so many years of twin rear shocks. But, before the 400 was even broke in, Bob crashed it and bent the front rim and forks. I fixed that up for him but his interests changed shortly thereafter (girlfriend) and he sold it and never owned another bike again. But I digress....

Once I got the red Yamaha, it saw a few years of riding around the farm, mostly in the cow pasture. There were plenty of ant hills and rocks to crash on and I did my share. Never really hurt myself or the bike much though. I never rode it on the street. By this time most of the electrics including the headlight and tail light were dead.

Somewhere during this time before graduating from college in 1977, I managed to melt a hole in the piston. The Yamaha shop in La Crosse helped me find a new oversized piston from a snowmobile. It was technically a 290cc piston with that motor's stroke. I'm not sure what the actual CC displacement is in the DT1-C though. I'd guess a little less since the stroke is fairly short.

Shortly after graduating college and moving to Milwaukee, I broke 2nd gear in the transmission. I took the engine/transmission to my apartment in Milwaukee and split it open to get to the broken gear. With the help of a Yamaha shop in Milwaukee, we managed to find a new gear (and all the other upgraded gears to match it) and I got it put back together.

After getting married (1978) and moving to Green Bay the bike saw only occasional use when we would visit my parents since the bike was stored there. Then, in 1984, we moved to Birmingham, Alabama after which the bike got very little use. Usually once or twice a year we'd make the trip from Alabama to Wisconsin so the kids could see their grandparents. That usually meant a few days of use for the Yamaha after which the fuel was drained, the tires bled down, and a little oil poured into the cylinder before it was covered up and put back into storage in a shed on the farm. There it would sit for a year until I visited again. It would always start with just a few kicks and run pretty well. It always smoked a lot (even for a 2-cycle) and needed carb work after replacing the piston but I was young and foolish and had too many other things to do in those days.

The yearly visits went on for almost 30 years before I managed to get it hauled back to Georgia for the restoration. I did bring just the engine back to Georgia in 2007 or 2008 to do some cosmetic work on it. I hauled it back in the trailer I towed with my Goldwing.

Click here to see 40 years of motorcycle evolution (my red 1970 Yamaha 250 sitting along with my green 2010 Kawasaki KX-450F and Mike's blue 2006 Yamaha YZ-450F).

Dateline: November 2013

The Yamaha comes to Georgia in October. In November I took the bike all apart and made the initial list of parts I would need (tires, bolts, seals, axle, etc.). Once I got it apart it was obvious that there were quite a few tired parts. I decided to strip it to the frame and get the frame powder-coated but only got as far as "strip it to the frame". I was able to track down a lots of the parts I needed on some vintage motorcycle parts websites (www.nwvcp.com for example) so I started buying parts as I could find them.

Dateline: August 2014

Finally in August 2014 I got the DT1 frame along with the frame of a mini bike I built for the grandkids powder-coated. I finished the mini-bike project in time for the October 2014 trip to Wisconsin but the DT1 is still in pieces.

Dateline: December 2014

For whatever reason, I got the urge to work on the DT1 during my 2 weeks of vacation around Christmas. Since I had many of the parts it was time to start cleaning up the parts I would re-use and get the forks rebuilt (they were leaking badly). It probably goes without saying but getting 40 years of dried grease, oil, dirt, and cow s**t cleaned off every little part is slow going. Most of the bolts, spacers, washers, etc. that look to be made of dull aluminum or steel turned out to be shiny chrome when I got them cleaned up. I was amazed at how well the chrome had survived all the years of being covered in muck. Yamaha must have poured the chrome on really thick! Along the way I did find some more parts that needed to be replaced and got them ordered.

Front Forks

The front forks were a real treat to work on. I'm pretty sure that the oil was changed in them at least once and I do recall replacing one of the fork seals many years ago. It was really obvious that this was NOT nearly enough. Aside from containing really smelly old oil there was also a good dose of sludgy muck in the bottom of each fork. I'm amazed that they worked at all. It took quite a while just to get them apart and even longer to dissolve all the sludge out of the bottom. I finally did get them cleaned up. I need to bead blast the outer tubes and repaint them before re-assembling. The outer (lower) tubes had lots chips in the paint that had started little rust pockets after years of stones, barbed wire, dirt, and general abuse.

Triple Tree

I've cleaned and prepped the upper and lower components of the triple tree and it is ready for paint as well. I've also modified the front fender mount to make it a bit less of a kludged together mess. It will also get some paint (for the first time) so it will look better as well.

Front and Rear Brake Hubs

The front brake hub has been cleaned and prepped. It and the brake shoes (the bike has drum brakes on both ends) were in good condition after removing the grease and grime. A little steel wool polished up the old aluminum really well. The rear brake hub has also been cleaned up. New brake shoes were installed.

Rear Sprocket Hub

The chain sprocket hub on the other side of the rear wheel was dismantled and cleaned. The bearing in it is really rough so it will have to be replaced. I already have a new 44T sprocket for it (along with a matched front sprocket).

Rear Axle

I had previously noted that the rear axle showed signs of wear where the bearings ride but thought I might get away with using it anyway. Yamaha doesn't make the axle any longer. But then I discovered that it was also bent so it will have to be replaced. I think I have located one on eBay but it is $30. Seems like a lot for an axle but what choice do I have?

Dateline: January 22, 2015

Have been steadily working on cleaning, sand blasting, painting, and assembling. Am finally making some progress. I keep finding parts that are either wrong or missing though. I've had to place several orders for odds-n-ends parts over the last 10 days.

Rear Brake Pedal

After getting it primed and painted, I went to install it and realized that the bushing that was probably left in the frame when I had it powder-coated was missing. My fault. I should looked more closely. As it turns out, it is hard to find and really expensive. I guess I will turn a new one from a scrap chunk of oil-bronze.

Rear Axle

I've temporarily stuck all the parts on the axle shaft now that I finally have a new (used) one that isn't bent. Still need to clean the rims and spokes and get the new tires mounted.

Steering Head

I went to install the steering head tonight after getting everything painted. I then discovered that somehow during the disassembly process I managed to lose 2 of the 22 ball bearings that go at the top of the steering head shaft. I scrounged around in the garage where I took it apart almost a year ago and did find 1 of them. But, whether I'm 1 short or 2 makes little difference. It won't work with missing balls. Luckily I can still buy them so I ordered a new set. The waiting game begins again.

Dateline: March 19, 2015

I've been getting a few things done again lately. I finally got the lower fork tubes blasted and painted. They look pretty good. I am happy with the color. I hae reassembled both forks using new seals and have re-installed them onto the bike. This let me then re-attach the headlight bucket. It's starting to look like a motorcycle again. I also blasted, painted, and installed the orignial battery box. It has never looked this good!

Next up will be the wheels and tires. I found a place overseas that offered new spokes for the DT1. The hard part was the 19" front rim. All of today's bikes use 21" rims. I'm still waiting for the new spokes to arrive. Then I get the pleasure of relacing both rims. I can hardly wait (sarcasm intended!).

The Levys