OzVMX Forum

Marque Remarks => Yamaha => Topic started by: John Orchard on December 30, 2018, 11:23:43 am

Title: Yamaha DT1, I have found a whole new interest & respect
Post by: John Orchard on December 30, 2018, 11:23:43 am
Well I acquired an old bike from the dusty back corner of my Brother-in-law's shed, turns out to be a mixture of DT1 & DT2, it has had so little use! The footpeg pins have less slop after 50 years than my bikes normally have after 6 months!

Not much wear but rusty as hell  :-)  So I have started researching parts & information for the DT's, man it is so interesting.  There must have been millions of them sold in the US; you can still buy heaps of stuff for them; new & used!

For a 1968 model Japanese machine, it was so far ahead of its time, and incredible better quality of materials than modern machines.

I'm interested in your stories relating to the early DT's ........
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: 80-85 husky on December 30, 2018, 05:27:15 pm
only rode an RT 360..terrible bike...outrageous power (for the time) tallll gearing, bone crunching shockers and forks but the brakes worked. like the QE2 in dimensions and so hard to make it turn. raised on ts 125 185's it was a massive aircraft carrier to me !  i burned myself on the pipe somehow?? so no real fond memories and i vaguely remember it lunched the box liek other yammies of the time...
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: Hoony on December 30, 2018, 09:23:16 pm
get in touch with Firko (Mark Firkin) on Facebook
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: Oldfart on December 31, 2018, 09:21:45 am
John... my first bike was a DT-1  250 . It was bullet proof and I served me well.

Enjoy
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: jimson on December 31, 2018, 10:13:58 am
A very cool model, as it was the starting point for many dirt loving road users, and it was at the time capable in the dirt apart from the frame needing a bit of modification to make the engine lower for better handling. The engine is bullet proof. Yamaha really ticked the box in 68 with these lol ????
jimson
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: sleepy on December 31, 2018, 10:49:06 am
Great machines. Had a DT1 as a teenager with a GYT kit. When I got my license at 17 I bought a used RT3 as my first registered bike and I still have have it today. Restored it as close to original as I could 2 years ago.
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: David Lahey on January 01, 2019, 11:08:12 am
I bought a DT2 in 1977. It was in original condition and had no problems mechanically and looked like it had only been used on the road. I had wanted a bike to ride to work to avoid putting too many kms on my IT175 and for that purpose was a good choice. I did a cosmetic resto on the DT2 and remember being able to walk into my local Yamaha shop and buy a complete new seat for it. I rode it to work for a while and even did some sort of all-day nav run on it (12 hour road trial?) but didn't fall in love with it. The main issue for me was the scary-poor handling in the dirt which in hindsight would have been greatly improved with a 21" front rim and decent tyres. As well as the standard Yamaha exhaust, it came with a Bassani exhaust and a bigger carby? (Sleepy may remember). The pipe gave it more top end power (and noise) but with the standard (fairly high) gearing it was hard to keep it in the fat part of the rev range even on the road.
Sleepy's RT3 (mentioned in a previous post) had been very well developed in the power and handling department at the time and was a far more enjoyable bike to ride than my standard DT2.
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: sleepy on January 01, 2019, 01:39:47 pm
Got a Two Wheels mag issue No5 here with a road test of what look like a 69 DT1. Can I post it here or does that cause a copyright problem?
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: John Orchard on January 01, 2019, 02:13:39 pm
Got a Two Wheels mag issue No5 here with a road test of what look like a 69 DT1. Can I post it here or does that cause a copyright problem?


Go for it, l'll represent you in court ;-)
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: sleepy on January 01, 2019, 02:59:57 pm
Just got to work out how. I can scan the pages but what is the best way to show them?
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: sleepy on January 01, 2019, 05:20:06 pm
Scanned the 5 pages I could email them. Send me a PM with a real Email and I'll send through.
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: dont on January 02, 2019, 08:16:58 am
I think Jim Scaysbrook did a test of a factory kitted dt1 when they first came out ???? He won a motocross (natural terrain in those days) championship from memory.
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: fred99999au on January 02, 2019, 05:06:30 pm
First bike I ever bought, and still have it. It looks a little sadder these days.

Played with the exhaust port until it could only be push started when I was a kid. I do have a new cylinder and piston for it thought and plan to do something with it at some point.
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: Mick D on January 11, 2019, 10:23:34 pm
Hi John,
your really going to enjoy this Cycle World article if you don,t already have it.

http://www.eurospares.com/graphics/chassis/LightWeightWeaponCycleGuide.pdf (http://www.eurospares.com/graphics/chassis/LightWeightWeaponCycleGuide.pdf)

Cheers
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: topari on January 11, 2019, 10:47:20 pm

http://www.eurospares.com/graphics/chassis/LightWeightWeaponCycleGuide.pdf (http://www.eurospares.com/graphics/chassis/LightWeightWeaponCycleGuide.pdf)


Good article, but I see the beginning of the small under-powered drum brakes. My 250B has a 160mm front and 150mm rear, compared to my KDX175 which had 110mm front and the KDX200 at 120mm.  I reckon if they had stuck to big drums the disk brake evolution would have been deferred for sometime. I also like cush hubs. Under very slipper conditions they work well. Love my old honda XL350.
Title: Re: Yamaha DT1, I have found a whole new interest & respect
Post by: John Orchard on January 11, 2019, 11:39:02 pm
Wow, very interesting, thankyou very much. lt has given me some ideas, some mods are out of my price-range, l've even initiated some mods that they didn't do.

lt is very interesting playing with an old trailbike, use of modern designs make it easier to develop the bike :-)

l hope to get out for my first shake-down ride in about 3 weeks, l'll report back. Thanks again.