Yamaha – AT – CT – DT – RT

In the really early 70’s… Yamaha had these as their dirt bikes:
– AT1 – 125cc
– CT1 – 175cc
– DT1 – 250cc
– RT1 – 360cc

All were 69-71 era, piston port motors, before Yamaha really knew what dirt bikes would become. And all were relatively about the same dimensions, just different weight.

Lately I’ve been regretting buying my 71 CT1 since it’s lacking the newer technology compared to the late 70’s. I really wish I had bought a 78-82 dt175 instead; way better suspension and faster.

Regardless… I’ve been looking at ways to make mine better from a performance and suspension standpoint and after finding all these cool images, it gives me some solid inspiration. Some of these bikes below are badass! This is what I’m thinking:
– already have pod filter and jetted carb
– GYT expansion chamber exhaust
– aluminum rims. small front hub. no front brake
– plastic front and rear fender
– smaller front gear. bigger rear gear
– front end from a YZ or MX
– maybe take all my lights off and put a number plate on it

Yamaha had a power kit from the factory called “GYT”. (Genuine Yamaha Tuning)

You could walk into a Yamaha dealer in 1970 and get a new piston kit / carb / gear / exhaust (all yamaha parts) to make it go faster. I’m trying to find some of this stuff on eBay but its super rare.


FYI – the hot exhausts were:
– hooker
– DG performance
– torque engineering
– bassani
– moto tech


11 responses to “Yamaha – AT – CT – DT – RT”

  1. Kansas Larry says:

    You might check the AHRMA website classifieds. From time to time they have parts listed you might be needing.

  2. ed says:

    Thanks Larry.
    I’ll definitely take a look at the AHRMA web classifieds.
    Did you ever have any old 70’s Yamahas?

  3. Louis says:

    Hi Ed. I also have a 1970 Yamaha RT1. Thanks for the good info on the aftermarket parts for these bikes. If you don’t mind, shoot me an email at louisandellen@yahoo.com.

  4. Doug says:

    Yamaha dealers used to retorfit the new MX with ODO/TACH & lights for customers who wanted them. I had one, off the Showroom floor, licensed for street and a screamer on the sandhills on weekends. I kept it for years & sold it when I got married (right after restoration). Wish I had held on to it. It was a heavy beast but she was my Mistress.

  5. Pascual Tufano says:

    Where i can find for my yamaha 360 the “DT-1 GYT Kit” …
    somebodycan help me to find the parts needed to convert my 360 ?
    Thanks for your help

  6. marco says:

    hi guys,i am going to buy a 1970 yamaha ct1 175 for 1 grand. the bike is pretty good condition considering it was born in the 70S, it run and stars almost at frist kick. it has two pipes on its heads but one wasn’t plugged, he said it was normal,was it? can you guys please make this clear for me? thank you.

  7. Ed says:

    Marco – 1 hole should have the spark plug and 1 hole should have a plug

  8. marco says:

    it was so,hopefully it will a good one.
    thank you.

  9. What’s up,I check your new stuff named “Yamaha – AT – CT – DT – RT – Chin on the Tank – Motorcycle stuff in Philadelphia. Brappp” like every week.Your story-telling style is awesome, keep doing what you’re doing! And you can look our website about cast love spells.

  10. Schafer says:

    I have been tryu G to find a carb for my dt 250 1973 and it’s pretty hard to find I was wondering if a ct would work with it as well

  11. Michael G says:

    What does ‘CT’ meaN at the end of my bin?

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