I've started pulling two 71 AT1s and a DT1 apart to figure out what all they need mechanically.

Intro thread here: yamaha-enduros.com/index.php/forums/fng-...hen-there-were-three

I've dubbed them "II Triello":




I've started on getting the tank from the 250 cleaned up. I'd rather not paint it if I don't have to and also rather, like the sun bleached color on the top of the tank. There's still a lot of dirt in the paint but this image shows a first clean/polish/wax. The inside of tank on the 250 is amazing.

The first of the AT1s will soon be mechanically sound. I don't think I'll paint anything on that bike. It's pretty nice the way it is. It's almost like someone took a new bike and built it to look old.

The AT1 that I haven't started with yet, is in even better condition consmetically.


My first question:

What do you all generally set the idle at? The book says 1200-1300 rpm. I can get it down to about a stable 1500ish.

I should probably mention that I have an El-Cheapo Chinese carb temp installed while I rebuild the Mikuni. It's new but none the less...

There's no perfection to idle speed, and the tach's obviously aren't digital so I like to see the tach needle waving around the 1300-1600 mark.

Clutch pack showed up for the AT1.



I'll get these soaking in oil tonight.

Does anyone have a definitive preference for ATF over 10w-30? I wonder how the various seal materials react to ATF.

Like Apex said for idle, mine generally sits around 1500, any lower may sound a little better but is more prone to stalling or dying with the clutch pulled in and transmission in gear.

Most of us use wet clutch compatible 10w30 of choice, have heard of people using ATF and it working fine, I personally don't see the advantage but I'm not racing either

Great looking bikes, good back story, fun to see them clean up so well!

Timely tip. I nearly soaked them in Valvoline. I've got them in Rotella 10w-30.

I got all set to pull the clutch cover yesterday when I caught a note about Yamaha No 5 sealant. My gasket set should arrive today but it'll be a day or two before the sealant arrives.

Any tips on the clutch swap that I should know?

I'm aware of the possibility of a 'hidden' screw behind the oil pump that has to come out to separate the cover. Are there any other surprises?

Personally the Yamaha paper gasket alone has sealed just fine for all my clutch covers with no leaks. I think the Yamabond is for if you split the cases. You do need the thickness of a gasket in the assembly. No other surprises to speak of, I take the kickstand bracket off the smaller bikes which makes it much easier to get the cover off without harming the kickstart seal.

Is there supposed to be a catch or a spring between the float and the needle in the carburetor of the AT1?

The needle with have a lightly spring loaded button in it's center but no clip anywhere. Those clips on larger carb float needles are only to make it easier to assemble as far as i can see as do nothing except limit open travel but doubt the float arm on those drop far enough to let the clip take over.

Copy. Thanks!