DT 250/400 tank

[Leslie]

Hi I am fitting a 76 DT 250/400 tank to my tracker, The tunnel of the tank is too narrow, has anyone got around this problem, as i have seen plenty on the forums with the DT tank conversion, I thought about spreading the tank, but the fear of creasing the steel is putting me off.

 

[Downeaster]

As far as I know, it requires major surgery: cutting out, widening and re-welding the tunnel. That's the only thing that stopped me from doing it as I think the result is GORGEOUS!

 

[Leslie]

As far as I know, it requires major surgery: cutting out, widening and re-welding the tunnel. That's the only thing that stopped me from doing it as I think the result is GORGEOUS!

Downeaster you are correct, the tank is with my local fabricator, he is cutting and i will try it before it is welded up and painted. I will only be riding it in the summer with short trips into Derbyshire & Lincolnshire.

 

[willis]

Would the tunnel fit over the backbone if the cup mounting style wasn’t on the tank or frame? Thinking along the lines of mounting tabs welded on the tank to bolt to top of the backbone perhaps.

 

[Leslie]

Would the tunnel fit over the backbone if the cup mounting style wasn’t on the tank or frame? Thinking along the lines of mounting tabs welded on the tank to bolt to top of the backbone perhaps.

Willis, Keep an eye on this post as i am altering the tank as we speak.

 

[Raymond]

Downeaster you are correct, the tank is with my local fabricator, he is cutting and i will try it before it is welded up and painted. I will only be riding it in the summer with short trips into Derbyshire & Lincolnshire.

I expect it will be short trips. My DT400 used to run onto reserve before 60 miles. Mind you, that was a thirsty stinkwheel and petrol was cheap in the '70s.

And your tank will have a reduced volume; will look luvverly but bike will be a bit of a forecourt Queen?

 

[Leslie]

Would the tunnel fit over the backbone if the cup mounting style wasn’t on the tank or frame? Thinking along the lines of mounting tabs welded on the tank to bolt to top of the backbone perhaps.

Willis I have had to cut the tank, 12mm/1/2" app each side of the bottom of the tank, also I am going to have to get a smaller petcock

 

[Leslie]

it fits perfect now and the position doesn't effect the steering, just the DT petrol tap is too long, I will be looking for a shorter petcock.

 

[Raymond]

British bikes often have smaller, simpler taps. I bought a petcock for the RE Bullet from Feked - and they have a few styles.

 

[Downeaster]

Nice!

 

[Leslie]

Got my petrol tank back from the paint shop (Vale Paints Meden Vale) info@vale-paints.co.uk

 

[Leslie]

I expect it will be short trips. My DT400 used to run onto reserve before 60 miles. Mind you, that was a thirsty stinkwheel and petrol was cheap in the '70s.

And your tank will have a reduced volume; will look luvverly but bike will be a bit of a forecourt Queen?

Raymond I live central to several bike meets, plus Donnington Cadwell & Mallory, not to mention Matlock possibly the best bike meet in the UK.

 

[Leslie]

I am getting there with the bike, slowly, just minor works around the tank/seat

 

[Leslie]

Lads i need smaller coils as I have changed my tank and the old ones are just too big, any suggestions

 

[Signal]

Without seeing the size you have to work with its hard to offer anything other than generalisations.
Here are my ideas:
If your bike is not rephased is one dual output coil easier to fit under the tank.
I cant think of any small 3ohm coils of the top of my head but have a look at electrex world they have smaller sized coils just make sure the resistance is correct. IE not a CDI coil.
Can you remount the coils you have differently to suit the space you have. I did this on my tracker with an Omars tank.
I have used after market car coils on my road XS 650 using custom brackets . Not the big ali can type coils that Grandads Zephyr had much more compact.
Last alternative: massage the tight spots out of the tank with a hammer. I Did this to a CB900f tank to get it on a XS 850 frame

 

[Leslie]

Without seeing the size you have to work with its hard to offer anything other than generalisations.
Here are my ideas:
If your bike is not rephased is one dual output coil easier to fit under the tank.
I cant think of any small 3ohm coils of the top of my head but have a look at electrex world they have smaller sized coils just make sure the resistance is correct. IE not a CDI coil.
Can you remount the coils you have differently to suit the space you have. I did this on my tracker with an Omars tank.
I have used after market car coils on my road XS 650 using custom brackets . Not the big ali can type coils that Grandads Zephyr had much more compact.
Last alternative: massage the tight spots out of the tank with a hammer. I Did this to a CB900f tank to get it on a XS 850 frame

Without seeing the size you have to work with its hard to offer anything other than generalisations.
Here are my ideas:
If your bike is not rephased is one dual output coil easier to fit under the tank.
I cant think of any small 3ohm coils of the top of my head but have a look at electrex world they have smaller sized coils just make sure the resistance is correct. IE not a CDI coil.
Can you remount the coils you have differently to suit the space you have. I did this on my tracker with an Omars tank.
I have used after market car coils on my road XS 650 using custom brackets . Not the big ali can type coils that Grandads Zephyr had much more compact.
Last alternative: massage the tight spots out of the tank with a hammer. I Did this to a CB900f tank to get it on a XS 850 frame

My engine spec, so a twin coil set up is required

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All casings were vapour blasted and refinished.