BAck in 1976, Yamaha made a ton of cool accessories for our bikes. If you want to know what I mean, try downloading the accessory catalog in the workshop! What I am specifically talking about is one of these:



Seriously cool and apparently either very popular (not many NOS seen) or not popular at all (hard to find them even used!). So Vinnie had one of these babies on his "Mountain Bike" and probably didn't even now it was a factory tank! The neatest thing about them is they fit on the stock mounts and use a stock petcock, so you continue to have an operating reserve! Most aftermarket plastic tanks only have off and on petcocks. Some do have two petcocks, but then you have routing issues.

In any event, I found one, complete with a nasty petcock and functional cap. So darn cool I can hardly ride without shades at this point!



it fits like it was made for the bike (it was) and gives you 3.7 gallons of go juice! The only technical issue is you HAVE to fill your oil tank at every fillup or you WILL run out before the second tank hits reserve. Don't ask me how I know this little tidbit . . .



This bike was being purpose built to ride with GruppeTAT on the Trans America Trail. Fuel capacity was going to be quite an issue with long sections in Nevada and Oregon without fuel stops. But I digress. If you want the teaser for THAT story, you can see a short write up HERE.

So as luck would have it, in the process of working on the bike, I had the cap off. Then the dog ate the cap (or so I suspected). Of course, Yamaha used a completely proprietary cap size in the 70's and NOTHING I could find anywhere even came close. I knew that Dman had fashioned a metal cap on his copy of the tank, but I needed something even cooler.

The fix will be in the next post!

In our last installment, we showed you the basic install of a factory desert tank.

After you lose the cap - which tended to leak a bit anyway - you have a problem. Nothing else fits. So what is an enterprising Enduroholic to do? Get a different tank? I think not. Let's get creative!

First - you take the one of a kind vintage fuel tank and set it on the bench (after cleaning out all the fuel!!!!) and get out the cutter . . .


After you get to this point, you have probably needed a couple of shots to keep your nerves calm. You have just ruined a one of a kind vintage tank. There is no turning back now. Note the little circle which mysteriously appeared? That is the template.

You need to find the largest, flattest part of the tank and then after you get that done, you CUT IT EVEN MORE! :sick:



Holy Crap, Mako - have you lost your mind? No I haven't .

Before you cut the big hole, you have to make a purchase from Clarke Manufacturing.

This is two Clarke products. A Dry Break Cap (DBCC) and a Dry Break Backup Ring (1504). I was actually able to test fit things at the Clarke Manufacturing Plant in Mollala, Oregon . The owner took me to the shop and we verified that this crazy project would work before I bought the parts! Great people and highly recommended vendor!

But I digress. Back to the Holy Tank, Batman.

This picture shows the ring sitting on the top of the tank and being used as a template to mark the screw holes for installation. The ring is split so you can stick one "end" in and kind of screw it into the tank. It sits on the inside and provides the backing for the cap plate to screw into!

So now we add the conversion cap . . .

don't forget gaskets inside and out, then carefully and equally tighten down the nice socket head screws so everything seals up. Add the cap and a breather hose (not included).



More to come!

Of course any story with Mako involved would be rather boring without the "issue" statement.

So this bike, with this tank took on the Western section of the Trans America Trail, from Monticello, UT to Port Orford, OR and the tank was flawless. Unfortunately sometimes human error just can't leave a good thing alone.

In Canyonville, OR, We stopped for fuel and lunch. Dman was in charge of topping off the tanks. APPARENTLY, he forgot to tighten the cap and 20 miles or so later, I begin to smell fuel. Lots of fuel. I look down and see this:

That 's Dman taking responsibility for the freak accident . . .

Of course it is a special cap. Of course we are 20 miles out into no man's land, with 80 miles to go. Being of the mindset of Duct Tape . . .


A plastic lunch baggie, secured in place with a Zip Tie sealed things up well enough for the roads we were traversing to keep the wet stuff in the tank where it belonged. It also, because of the large threads on the neck, allowed me to carefully unscrew the bag cap and reinstall after the one fuel stop we made!

This solution would work on most modern bikes with the plastic caps as the necks are very similar if you ever get yourself in a bind like this.

I ultimately ended up buying a nice aluminum cap as a replacement which sorta, kinda made the event OK . . .

In any event, a baggie will keep you riding even in the company of these bad dudes!

Folks,

I have an old Don Vesco "Skinny-Fat" tank. Right now, I am painting it (using Krylon Fusion paint). When it's done, I will be able to trade it between the RT-3 and the 250MX, depending on what's going on at the time.

Hammer

The Vesco and the Malcolm Smith tanks are very similar and will both work. Here is one of them (I don't recall which) on a DT400. I think it is the Malcolm Smith.



And here is an RT with a different version which I believe to be a Vesco:

Hello fellow Enduro enthusiasts.... I am new to this site and know I'll be spending a lot of time here.

Back in the day, I had an original Yamaha Desert tank on my 1975 MX400B. It definitely "expanded my horizon". Alas, a lifetime and many moves later, the tank and I have since parted ways. I can't remember where it went and wish I still had it. Never the less......I have been searching high and low for another. If someone out there has one buried out in the shed or in the rafters of the garage......please contact me. Than you!

Welcome WFO. I don't remember a Yamaha tank for your bike. Most of the ones I have ever seen were an MS, Vesco, or Hanneman, we raced desert back then and that's what I remember. I have a couple of tanks in my stash I would get rid of.

I have a Yamaha desert tank available (like the one shown on Makotosun's bike)..... if you don't find what you want.

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