facebook1 youtube1 twitter1 instagram google plus linkedin1 pinterest1

logosmallNOTICE:  If you are not a free registered member of the site, you will not see the photos in the forum, and you won't be able to access our premium member content. Please consider joining our community!

Welcome, Guest
Username: Password: Remember me

TOPIC: 1971 at-1 first bike thread

1971 at-1 first bike thread 16 Jul 2018 18:08 #1

  • Yojimbo
  • Yojimbo's Avatar Topic Author
  • Offline
  • Mini Enduro
  • Mini Enduro
  • Posts: 28
  • Likes received: 11
Hello everyone,
I recently acquired my first bike, a ‘71 at-1. I have zero experience with motorcycles. I have a lot of experience with bicycles, and a few summers ago, my brother and I built a number of motored bicycles with those chinesium 80cc two stroke kits. They were a lot fun, and they whetted my appetite for a real motorcycle, something I had always thought about, but for a number of reasons, never got.

A life long friend of mine is an enthusiastic rider, and always has 3 or 4 different bikes. I have always admired his collection, and skill with riding and wrenching. He and my brother both influenced my purchase. They both have enduros, and I’m looking forward to riding with them.

I am a pattern maker by trade, and have access to all manner of metal working equipment. I’m a fair wrench and painter, so I, along with my son, will be doing all the work on the bike. I plan on documenting the process of repair, tuning and cosmetic items with posts to this thread.

Thanks to anyone who is still reading

Jamie Galvin
The following user(s) Liked this Post: Snglsmkr

Please Log in or Create an account to join the conversation.

Last Edit: by Yojimbo.

1971 at-1 first bike thread 16 Jul 2018 18:11 #2

  • Yojimbo
  • Yojimbo's Avatar Topic Author
  • Offline
  • Mini Enduro
  • Mini Enduro
  • Posts: 28
  • Likes received: 11


Here is a link to a walk around video I posted to youtube

Jamie Galvin
The following user(s) Liked this Post: Badger52

Please Log in or Create an account to join the conversation.

Last Edit: by Yojimbo.

1971 at-1 first bike thread 16 Jul 2018 18:25 #3

  • Yojimbo
  • Yojimbo's Avatar Topic Author
  • Offline
  • Mini Enduro
  • Mini Enduro
  • Posts: 28
  • Likes received: 11
The oil injection has been removed from this bike. I have the tank, but not the Siamese fitting for the control cable that goes to the pump. A few questions:
Is the oil injection system reliable?
Is it worth getting the parts to make it work?
What fuel:oil ratio should I use if I’m not using the injection system?

Thanks
Jamie

Please Log in or Create an account to join the conversation.

Last Edit: by Yojimbo.

1971 at-1 first bike thread 16 Jul 2018 19:49 #4

  • JayB
  • JayB's Avatar
  • Offline
  • Site Contributor
  • Site Contributor
  • Posts: 32
  • Likes received: 17

Yojimbo wrote: A few questions:
Is the oil injection system reliable?
Is it worth getting the parts to make it work?
What fuel:oil ratio should I use if I’m not using the injection system?

Thanks
Jamie

Yes, a properly set up oil injection system is reliable.
You will have to decide if it is worth it. Total up the cost of the missing parts. Add your labor and time. It is convenient to have if you drive around on the road a lot.
For premix, I would use a good synthetic oil at about 40:1.
One caution, when removing the autolube system I have removed the little brass drip tube in the intake stream, for every ounce of power (don't believe it!).. That cylinder would probably still work fine as later models don't have the little tube sticking out in the air stream.
The following user(s) Liked this Post: Yojimbo

Please Log in or Create an account to join the conversation.

Last Edit: by JayB.

1971 at-1 first bike thread 16 Jul 2018 20:06 #5

  • Yojimbo
  • Yojimbo's Avatar Topic Author
  • Offline
  • Mini Enduro
  • Mini Enduro
  • Posts: 28
  • Likes received: 11
Thanks Jay,
The guy I bought it from told me 15:1, seemed ridiculous, and it’s crazy smoky. I’ll rinse the tank out and start fresh. I’ll also hunt down the gear required to make the oil injection work, seems too convenient to not use.

Jamie

Please Log in or Create an account to join the conversation.

Last Edit: by Yojimbo.

1971 at-1 first bike thread 17 Jul 2018 09:33 #6

  • Yojimbo
  • Yojimbo's Avatar Topic Author
  • Offline
  • Mini Enduro
  • Mini Enduro
  • Posts: 28
  • Likes received: 11
This bike is loud. I'm pretty sure the exhaust is not stock. There is an NOS performance exhaust for an at-1 on eBay that looks very similar to the one that came with my bike. Mine has what looks like a lawn mower muffler welded to the end of the pipe. It seems like cutting off the lawn mower muffler and replacing it with something is the easiest solution. Does this make sense, and if so, could someone recommend something to quiet this thing?

Thanks
Jamie

Please Log in or Create an account to join the conversation.

1971 at-1 first bike thread 17 Jul 2018 12:54 #7

  • Mothersbaugh
  • Mothersbaugh's Avatar
  • Offline
  • Collector
  • Collector
  • Posts: 614
  • Likes received: 246
Stock pipes come up on ebay every now and then. I've seen them listed for as much as $250, but I've bought a couple for under $100. And that's with the chrome guard and all.
The pipe looks like it might be worth looking into keeping. Someone will chime in here with thoughts on the silencer.
+1 on the autolube oil system. If you really want it to perform well, there's a guy on here, DEET, who rebuilds the pumps with all new parts and sets them up to work perfectly for a reasonable fee.
And in the meantime, industry standard seems to be 32:1. I think 40:1 is a little thin.
Welcome. I have three AT-1's, including two 71's, and I like them a lot!
The following user(s) Liked this Post: Swoop56, Yojimbo

Please Log in or Create an account to join the conversation.

1971 at-1 first bike thread 17 Jul 2018 14:34 #8

  • Yojimbo
  • Yojimbo's Avatar Topic Author
  • Offline
  • Mini Enduro
  • Mini Enduro
  • Posts: 28
  • Likes received: 11
Thanks Mothersbaugh,
I'll go 32:1, and I'm actively looking for the parts required to reinstall the oil injection. I'm still prioritizing the work that needs to be done. I think I'm gonna try one of those $15 cans off eBay:

.

Anybody have experience with them?

Thanks
Jamie

Please Log in or Create an account to join the conversation.

1971 at-1 first bike thread 20 Jul 2018 19:42 #9

  • Yojimbo
  • Yojimbo's Avatar Topic Author
  • Offline
  • Mini Enduro
  • Mini Enduro
  • Posts: 28
  • Likes received: 11
A little update, figuring out how to ride in my yard, very fun.
I've been sorting out little things, it was stalling after riding for a little while. It would lose power, stall, and not restart till I waited a few minutes. My brother was correct when he told me to loosen the gas cap. I think I'm gonna get one from yambits. I'll wait until I have a list of things I want from them.
I removed the riser things on the bottom of the rear shocks. Ride height is better now.
It runs pretty good, starts pretty good now that I've done it a few times, idles good, seems to make plenty of power. Clutch and transmission seem to work good. I'm not able to critique properly given my lack of experience, but it seems like I did ok.
The paint is so ugly that Hipsters would like it, so I at least gotta get rid of the copper color.
Got some electrical work to do before it'll inspect, so I guess that's next.
Thanks
Jamie

Please Log in or Create an account to join the conversation.

Last Edit: by Yojimbo.

1971 at-1 first bike thread 20 Jul 2018 21:23 #10

  • MarkT
  • MarkT's Avatar
  • Offline
  • Site Contributor
  • Site Contributor
  • Posts: 4141
  • Likes received: 1844
Yamaha still sells the gas cap... and a lot of other parts. Can't hurt to check Yamaha price as sometimes the original new is cheaper than aftermarket or "NOS" on ebay.

Congrats and have fun!
The following user(s) Liked this Post: Hammer, Yojimbo

Please Log in or Create an account to join the conversation.

1963 YG1-T, 1965 MG1-T, Allstate 250, 1970 CT1b, 1971 R5, 1973 AT3MX, 1974 TS400L, 1975 RD350, 1976 DT175C, 1976 Husqvarna 250CR, 1981 DT175G, 1988 DT50, 1990 "Super" DT50, 1991 RT180, 2017 XT250
Moderators: VinnieDEETyamadminDmanEnduronutMakotosunDevinJames Hart
Powered by Kunena Forum