Fuel tank issues

Related:
Create New Tag

8/10/2019 10:01 PM

Hi guys, l need info on a new replacement fuel tank for 1979 YZ250f as my searches have been unsuccessful. As the '78 model tank does not fit can anyone confirm if a '80 tank will.
Re gards Michael

|

8/11/2019 9:33 AM
Edited Date/Time: 8/11/2019 9:33 AM

An 1980 may fit but most definitely are not the same as a 79 tank

|

8/11/2019 11:27 AM

Your welcome (click pic)


|

I was G before the "moto drive" to Vital

8/11/2019 11:43 AM

disregard, I was thinking 78 would. I know a 1980 will not.

|

I was G before the "moto drive" to Vital

8/11/2019 12:53 PM

Hey guys, thanks for your input. The tank I have is totaled. I found this bike outside leaning on a water tank post for at least two years. Will probably go for an '80 tank and modify the mounts if I have to. Am not concerned with different model tank as I ride the bikes I restore.
Regards Michael

|

8/11/2019 2:33 PM

twinshocks wrote:

Hey guys, thanks for your input. The tank I have is totaled. I found this bike outside leaning on a water tank post for at least two years. Will probably go for an '80 tank and modify the mounts if I have to. Am not concerned with different model tank as I ride the bikes I restore.
Regards Michael

Just be aware that the 1980 model dropped the tube enclosed shock that was used on the earlier models, and went to an open style frame in the back bone area. The '80 tank may not have a wide enough tunnel to fit the F frame.

|

8/11/2019 3:21 PM

Thanks again, looks like '78 tank and modified mounts.
Appreciated Michael

|

8/12/2019 7:32 AM

A 79 400 tank may be a closer fit if you can find it

|

8/12/2019 8:22 AM

Here is the run down on tanks.. I had a 79 YZ400 and have a 81 YZ465.

The 80/81 tanks won't fit. They are narrower at the tunnel since they relocated the shock to the back bone. I tried to mount a 80/81 465 tank on my 79 400 and it wouldn't fit (the 80/81 465 are 2.4 gallons while the 79 is 2.0) to get more capacity for the hare scrambles I was running.

The 77-79 tanks should fit. The 125 has a smaller capacity and the 250/400 are the same size. The 79 is shaped differently but the 77-78 should bolt on.

Clarke makes an aftermarket version if you are inclined to go that route. See the link below. just gas tanks has free shipping over 200 and is the best deal..

http://www.justgastanks.com/search.php?search_query=11430

|

8/12/2019 12:30 PM

Hey guys, am in luck!! Just purchased a used '79 tank in great condition for $160.00. Problem solved. Again, thanks for your help.
Regards Michael

|

8/13/2019 4:31 AM

Over the last 10 years that I have owned my '79 YZ250 I have used 4 tanks on the bike. Over the years, three of them have had cracking issues.The current tank has held up for the last two years. At one time, I used a tank from a '79 125 which held up fine but found a 250 tank later which is on the bike now. The other tanks are displayed as garage foder....HA!

|

Larry Navarro - Spring,TX. Damm glad to meetcha!

8/13/2019 5:14 AM

Plastic doesn't last forever even with all the UV stabilizers and other stuff they add to make it last. I had a mint looking 77 CAN AM MX3 black tank with a small crack near the petcock. It fell 3 feet of the shelf and shattered into pieces. I've had a few white tanks from the MX and TNT from the same time period and they were still soft and pliable.

|

8/13/2019 6:12 AM

Are there any dual leading front brake panels from a newer YZ that is a direct fit for the 79 YZ250?

|

8/13/2019 6:21 AM

Not really. When they went to 43mm forks they changed the clocking of the brake plate stay so the dls brake plates changed with them and don't work on the 38mm forks on the earlier years.

Every once in a while I see for sale a dls plate that people claim work on the older forks but I don't know what it is from, maybe an IT since they had smaller forks up till 84.

|

8/13/2019 7:02 AM

Thanks...it was worth a try!

|

8/13/2019 10:32 AM

I used a DLS setup from a '80 or '81(can't recall) on the 38mm forks I installed on my 100. The stock forks for the 100 are 36mm but I used the ones from my '79 250. I installed 43mm on my '79 and those are from a '82 with the side mounted lug on the backing plate.

|

Larry Navarro - Spring,TX. Damm glad to meetcha!

8/13/2019 10:57 AM

The 80 YZ465, 81 YZ250, 81 YZ465, 81 IT465, 82 IT465, 83 YZ125, and the 84 YZ125 all share the same part number for the brake shoe plate. Is this what you used?

|

8/13/2019 11:16 AM
Edited Date/Time: 8/13/2019 11:17 AM

Oops. Man my memory is going. Those are what you want to work with the earlier year 38mm forks. 80 and older forks. In 82 they went to the 3 o'clock clocking of the brake stay. My bad

|

8/13/2019 11:54 AM

Great info! I will see if I can find one at a reasonable price.

|

8/13/2019 1:27 PM

You guys really think the effort of a dls brake is worth it? I can't say I've ever felt one set up right. Of the good working YZ drums I've ridden, they weren't dls.They look cool though

|

8/13/2019 2:39 PM

I see no real advantage. My 81 dls is slightly better than the single arm that was on my 79. Way more of a PITA to set up though and ultimately not worth the extra effort.

|

8/14/2019 4:56 AM
Edited Date/Time: 8/14/2019 5:00 AM

450exc115 wrote:

I see no real advantage. My 81 dls is slightly better than the single arm that was on my 79. Way more of a PITA to set up though and ultimately not worth the extra effort.

Actually, the DLS system is very easy to setup All you need is silence in the garage, good hearing, a couple of wrenches and a helper to slowly apply the front brake lever.
Oh yes, use only OEM Yamaha brake shoes. Stopping power is greatly increased if adjusted properly.

Helpful hint: The short lever shoe must make initial contact of the drum.

|

Larry Navarro - Spring,TX. Damm glad to meetcha!