1971 Yamaha DT1 250 timing

[greg644]

If your out there lord I need help. I'm trying to get an old bike running for my grandson. The bike is for off road only, no electrical system other than ignition. In regards to timing a 1971 DT1F Yamaha and I have the following questions please:

-I have an ignition base with points and condensor that 2 of the 3 wound wire coils have been removed. Is this because only 1 winding is needed to fire the ignition? I asume since there are no lights or battery the other wound coils were removed?

-There are 3, wires soldered to the condensor, 1 going to the points, 1 from the wound coil and the other is loose. I think it should go directly to the ignition coil. Is that correct?

-Where can I install a kill switch?

-The bike does not currently have an ignition coil. Do I have to use an ignition coil for that specific bike or is a 2 stroke 6V coil universial. I assume it's a 6V?

-I'm thinking about removig the center spindle that has the point lobe on it from an extra magneto by drilling out the rivets. I plan to use this spindle as a tool to set the timing then remove it and install the magneto. If the lobs are the same and in the same relationship to the key on the crank I hope to avoid the "thru the slot timing issues". Am I missing something in this plan?

-Clymers keeps refering to the piston location for timing as BELOW top dead center, BTDC. I assume that is the same as BEFORE top dead center, BTDC?

I hope this was explained clearly.Thanks for taking your time to reply and any help ou can be. Greg

[Airhead]

If your out there lord I need help. I'm trying to get an old bike running for my grandson. The bike is for off road only, no electrical system other than ignition. In regards to timing a 1971 DT1F Yamaha and I have the following questions please:

-I have an ignition base with points and condensor that 2 of the 3 wound wire coils have been removed. Is this because only 1 winding is needed to fire the ignition? I asume since there are no lights or battery the other wound coils were removed?

-There are 3, wires soldered to the condensor, 1 going to the points, 1 from the wound coil and the other is loose. I think it should go directly to the ignition coil. Is that correct?

-Where can I install a kill switch?

-The bike does not currently have an ignition coil. Do I have to use an ignition coil for that specific bike or is a 2 stroke 6V coil universial. I assume it's a 6V?

-I'm thinking about removig the center spindle that has the point lobe on it from an extra magneto by drilling out the rivets. I plan to use this spindle as a tool to set the timing then remove it and install the magneto. If the lobs are the same and in the same relationship to the key on the crank I hope to avoid the "thru the slot timing issues". Am I missing something in this plan?

-Clymers keeps refering to the piston location for timing as BELOW top dead center, BTDC. I assume that is the same as BEFORE top dead center, BTDC?

I hope this was explained clearly.Thanks for taking your time to reply and any help ou can be. Greg

Hi Greg

1: Yes you only need the one coil on the stator plate, the others would have been for lights / battery charge etc

2: Yes the third wire would go the the ignition coil

3: A kill switch should ground out the small wire to the ignition coil, share the connection for the third wire as above

4: Use any coil you like either a new one or one from a small 2 stroke 6v machine

5: Thats a good plan, just check any numbers stamped on the two rotors match up

6 : yeah its before top dead centre, clymers goofed?

Try googling 'Energy Transfer Ignition'

[greg644]

Thanks for the info. I've ordered points, condensor and a coil, but..............I've got a line on a PVL electronic ignition system for the bike. We will see which gets here first and I will let you know how it works out. Thanks again for taking your time to help.

[greg644]

I am updating my own post in case anyone will find it helpful. The PVL elec ignition arrived and is correct for my bike. Came with ign module and coil. Installed it on my bike but would not start until I found a second timing mark lower on the stator for a counter clockwise rotating engine. Fired up! Now all that is left is to tune the new Mikuni (slightly larger than stock) carb that came with it. The original point system will be put on an extra engine I have decided to put together from spares. I may be asking for help with the tuning..but we will see. Greg

[Cynic]

Thats really good info. Its that kind of stuff that can really get someone out of a tough problem.

Glad its sorted.

[blackhat250]

Yeh greg" usefull info from a new member,,, well done

[usernameisavailable]

Just this week I rebuilt the motor of this exact model of bike. I bought it pretty cheap because someone had broken the piston rings. So I just put the rings in, and the bike fired right up. Next day, being yesterday, it wouldnt. I checked for spark but got small white sparks. So following clymers manual, started checking resistance. The book gives me resistance values for a m100-08 magneto, but my magneto is m100-16. Are the values going to be the same? Theres a red/white to black test which should have no resistance, but I am getting infinite resistance there. Is that my issue? Not sure how to proceed.

Thanks to anyone who can offer some advice

[Cynic]

Best advice is start from the beginning. In your own post after poping an intro up. It will make a huge difference to the replies you get. Here you may well get this and nothing more.