oil tank fittment question

iceteanolemon · Feb 23, 2013

quick question about the oil tank...

I sent mine in to CNW and they did a great job refurbishing it. I installed it back in and now were not going with the bottom mount and also adding the thin pad to the battery tray side and the thick underneath. I used the supplied isolated mounts etc and everything is tight and solid. Only thing I see is extra stress on the rear rubber mount. I forsee this one giving way soo since its stressed. I look behind the tank and there is no obstruciton creating this stress. I will stare at it a bit but though I would shoot the pic your way for any input etc...

Thanks for any input you can provide....

bwolfie · Feb 23, 2013

Is your wiring harness invading the neck space? Looks like it in the picture.

iceteanolemon · Feb 23, 2013

maybe, I will look again. Certainly looks like it in the pic. always a litle finnagling to get it right in assembly...

1up3down · Feb 23, 2013

yes, it does look stressed enough to have a couple rubber snubbers on hand for an annual replacement

mine looked the same so I drilled another hole about a 1/4 inch over to the right and it lined up properly

iceteanolemon · Feb 23, 2013

bwolfie said:
Is your wiring harness invading the neck space? Looks like it in the picture.

I just looked and the harness is a few mm not even touching. Just for grins I palmed the top of the tank and pushed it inward to destress the iso mount. Then in this position I looked at the front mount, low and behold the front mount was stressed.

My suspician is that when CNW re-welds the rear mount it may not be in the exact space again for reassembly. When I sent my tank to them the rear mount was cracked off. (That's the reason I sent it)

I think I will end up drilling a hole to mount it in a comfortable manner.

It bugs me to envision drilling holes in my frame hahaha but I don't have matching numbers or anything, it's all about making it fit right in the end.

B.Rad · Feb 23, 2013

Hello all.

I seem to be in the same boat here as Iced Tea. funny things with fitting oiltank to my 70 Fastback. mounting hole in battery tray seems right location. my problem is not so much misalignment but a extra 1/2" gap from back mounting tab to frame when using standard rubber mounts. front mounts OK, big gap at rear. Too much for rubber mount.

Is there missing a bent bracket similar to the one that carries the mounting pin on the other side (bolts on with 2 bolts) perhaps. this would appear to solve the problem

I will have to work out how to post photos. Technology dinosaur here, I dont even have a mobile phone.

If anyone could please post photos of well mounted pre 71 Fastback oil tanks please. details of fitment of front and rear rubbers would be very helpful. The parts book is a bit deficient on good assembly views here.

Thanks and best wishes to all
Bradley

iceteanolemon · Feb 23, 2013

If they made a slightly offset rubber mount it would be best. Maybe I can make a little bracket for the offset. Or maybe just leave it and replace the damn thing when it fails.

batrider · Feb 23, 2013

The directions say you might have to reposition the front mount slightly with a new hole. I had to do this but the rubber biscuit covers both holes. Did you do that? My rear one is straight.

pete.v · Feb 23, 2013

I simply use a bolt and a piece of rubber hose of choice. Snug it up to an acceptable level.
Those molded mounts suck.

cNw · Feb 24, 2013

iceteanolemon said:
bwolfie said:

Is your wiring harness invading the neck space? Looks like it in the picture.

Click to expand...

I just looked and the harness is a few mm not even touching. Just for grins I palmed the top of the tank and pushed it inward to destress the iso mount. Then in this position I looked at the front mount, low and behold the front mount was stressed.

My suspician is that when CNW re-welds the rear mount it may not be in the exact space again for reassembly. When I sent my tank to them the rear mount was cracked off. (That's the reason I sent it)

I think I will end up drilling a hole to mount it in a comfortable manner.

It bugs me to envision drilling holes in my frame hahaha but I don't have matching numbers or anything, it's all about making it fit right in the end.

Ice,

When we have to weld a new bracket on the rear, which is often the case, we use a fixture to locate it. In other words, its always in the same location.

As a first test you should remove the thin pad installed between the oil tank and battery tray. If you, when pushing the tank so that it unloads the mount in the back, get the front to move sideways, I suspect that there is a a bit to much space between the tray and tank.

Then as an option, do enlarge the rear hole a bit to allow the rubber mount seat without have a side load.

For the last year or so we are putting a different bend in the rear mount so drilling a new hole in the front is no longer necessary.

Let me know how it works out for you.

Thanks

Matt / Colorado Norton Works

iceteanolemon · Feb 24, 2013

Thanks for the reply Matt! I checked the rear side and when I look back there I notice the tank is pressed firm against the pad. Maybe this is how they always mounted and hats the reason the damn thing busted in the first place. I can't quite remember much.

Seems owning a norton is part riding, part mechanics, part engineering, and also forensics....

I might romance the hick rubber hose mehod, that sounds like a great idea.

ILLF8ED · Feb 24, 2013

iceteanolemon said:
quick question about the oil tank...

I sent mine in to CNW and they did a great job refurbishing it. I installed it back in and now were not going with the bottom mount and also adding the thin pad to the battery tray side and the thick underneath. I used the supplied isolated mounts etc and everything is tight and solid. Only thing I see is extra stress on the rear rubber mount. I forsee this one giving way soo since its stressed. I look behind the tank and there is no obstruciton creating this stress. I will stare at it a bit but though I would shoot the pic your way for any input etc...

Thanks for any input you can provide....

Your frame doesn't look quite the same as my '72. I just made some measurements for your reference. Measured across the center line of the oil tank cap I have 2.75" from the large center frame tube to to the outer frame tube. Also 6 7/8" from the weld of the outer tube to the large central tube forward of the oil tank cap to the rear plate behind the oil tank cap. Maybe the photo angle, but the angle of your rear plate to the large central tube looks to be less than 90 degrees.
What year model is your Commando and is this the original oil tank type to this year?

Onder · Feb 24, 2013

Have same CNW tank. Similar problem. I ended up using one of
the mounts supplied and one old one. The old ones are smaller or
shorter. The bike is not yet finished so I may fiddle with it more
before it goes on the road. It does seem rather flimsy what with
only the two thin mount brackets and no bottom one, doesnt even
yet have the weight of oil in the tank.

iceteanolemon · Feb 24, 2013

Onder said:
Have same CNW tank. Similar problem. I ended up using one of
the mounts supplied and one old one. The old ones are smaller or
shorter. The bike is not yet finished so I may fiddle with it more
before it goes on the road. It does seem rather flimsy what with
only the two thin mount brackets and no bottom one, doesnt even
yet have the weight of oil in the tank.

I actually left the thing on there, I think I will wear it out then do something about it. Maybe a small piece of stock and extend it a few mm. I have oil in mine and it is sitting pretty solid actually. I did add a thin pad to the side cover and it pushes againt the oil tank lightly, I wanted to avoid rattling and make for a padded snug fit on all sides.

cjandme · Feb 24, 2013

Maybe enlarging both holes or elongating them sideways would be enough to relieve the side load. Or matbe a smaller diameter bolt with the rubber hose and then a rubber washer behind the frame with a metal washer and an extra lock nut or nyloc on the bolt threads so it can stay on there without being tightened or torqued up really tight, but still be snug.

oil tank fittment question

Similar threads