Yamaha DT carburettor

[Coywolf 80]

7 minutes ago, stumfelter said:

The autolube feed goes directly into the cylinder on dt's. I knew that pipe on the carb wasn't right as I restored a 175 a few years back.

thanks for that mate....i have swapped the 1975 dt engine for an 1980 mx engine, i am using the dt carb on the mx.....on the mx it doesn't have that cylinder inlet.....maybe i need a mx carb.... 

[stumfelter 3,032]

1 minute ago, Coywolf said:

thanks for that mate....i have swapped the 1975 dt engine for an 1980 mx engine, i am using the dt carb on the mx.....on the mx it doesn't have that cylinder inlet.....maybe i need a mx carb.... 

On the mx it might be on the carb or as I said earlier it might be on the inlet manifold, not sure as I've not restored one of them!

[stumfelter 3,032]

Just checked and on the mx the carb has an autolube inlet where you have put the red circle in your picture.

[Coywolf 80]

13 minutes ago, stumfelter said:

Just checked and on the mx the carb has an autolube inlet where you have put the red circle in your picture.

thanks bud for your research on this.....much appreciated mate...... 

[mC HULL 10,398]

the dtr has pre mix aswell as paulus says just put 2 stroke in your fuel i always use a 100 ml to 5 litre jerry can 

[Coywolf 80]

5 minutes ago, mC HULL said:

the dtr has pre mix aswell as paulus says just put 2 stroke in your fuel i always use a 100 ml to 5 litre jerry can 

i think that is a bit to lean a mix for an old air cooled engine at 50.1 mate....

[Chid 6,372]

10 hours ago, Coywolf said:

i think that is a bit to lean a mix for an old air cooled engine at 50.1 mate....

32:1 on something that old od say though with modern oil 50:1 might be ok .. Maybe @paulus might know 

[downsouth 6,817]

15 hours ago, Coywolf said:

i think that is a bit to lean a mix for an old air cooled engine at 50.1 mate....

Most 70s 80s Air cooled stuff runs on 2%or 50.1 unless its been highly tuned Even the highly tuned kits that put on our  air cooled scooters only go to 3%

[paulus 26]

9 hours ago, Chid said:

32:1 on something that old od say though with modern oil 50:1 might be ok .. Maybe @paulus might know 

 32-1. Leave the needle alone, leave the pilot jet alone. Tune with the the main jet and air screw, The plug will tell you if the mixture is correct. a nice medium brown is what you are after. The mixture will need altering depending on what you are doing with the bike. If you are racing it then you might need to go up to 20/1. Trial riding then 32-1 is fine. That's using a mineral based oil, 

[poxon 5,555]

10 minutes ago, paulus said:

 32-1. Leave the needle alone, leave the pilot jet alone. Tune with the the main jet and air screw, The plug will tell you if the mixture is correct. a nice medium brown is what you are after. The mixture will need altering depending on what you are doing with the bike. If you are racing it then you might need to go up to 20/1. Trial riding then 32-1 is fine. That's using a mineral based oil, 

mate 

[poxon 5,555]

Another thing I’d like to add is E5 don’t do these old 2strokes much good they like high octane fuels. 

[downsouth 6,817]

6 minutes ago, poxon said:

Another thing I’d like to add is E5 don’t do these old 2strokes much good they like high octane fuels. 

All the scooter lads use E5.Its the more modern E10 with the higher ethonol content that we avoid.

[poxon 5,555]

2 minutes ago, downsouth said:

All the scooter lads use E5.Its the more modern E10 with the higher ethonol content that we avoid.

Feeling like a right twat now I meant e10 but put E5 like a spaz you are correct mate 

[downsouth 6,817]

4 minutes ago, poxon said:

Feeling like a right twat now I meant e10 but put E5 like a spaz you are correct mate 

I was thinking f**k have I been doing it wrong.Ive had all my scooters rebuilt with Ethonol resistant seals and pipes but still dont use the E10 stuff as Ive heard it absorbs water too if its left sitting in the tank for too long.

[poxon 5,555]

10 minutes ago, downsouth said:

I was thinking f**k have I been doing it wrong.Ive had all my scooters rebuilt with Ethonol resistant seals and pipes but still dont use the E10 stuff as Ive heard it absorbs water too if its left sitting in the tank for too long.

I think all fuels don’t last long now days I used super unleaded 97/97ron to get my little project going but that’s still got ethanol in it….few of my mates who run 2stroke enduro bikes told me to run race gas on the little kx I’ve got but don’t think my pockets are that deep and feck knows we’re id get it from or if I can store it