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2 stroke mix CR250M 73
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Author:  Uncle Dave [ Fri Jan 18, 2013 10:34 am ]
Post subject:  2 stroke mix CR250M 73
Can anybody tell me what mix 2 stroke mix I should be running?

The 73 manual say 20 : 1. A friend recommended 50 : 1 with modern 2 stroke oil.

Thanks in advance
Clive
Author:  Gary Starr [ Fri Jan 18, 2013 11:10 am ]
Post subject:  Re: 2 stroke mix CR250M 73
I run 32:1 in my MR and it seems fine using Hondas 2 stroke oil. 50:1 no matter what oil you use does not seem to be worth taking a chance IMO.
Author:  ohiomotoxer [ Sun Jan 20, 2013 10:28 pm ]
Post subject:  Re: 2 stroke mix CR250M 73
I ran spectro at 32:1
I also ran a reed, radial head and grafted a CR125 ignition to mine.
Points wise 1.8~2.0 BTDC worked fairly well.
Author:  rayivers [ Mon Jan 21, 2013 4:37 am ]
Post subject:  Re: 2 stroke mix CR250M 73
Quote:
I ...grafted a CR125 ignition to mine.

Was that difficult to do, and did it work well? I assume a later CR250M CDI ignition wouldn't work? I've searched the Web many times but this is the first I've heard of anyone fitting a CDI ignition to an early CR250M motor.

Ray
Author:  ohiomotoxer [ Mon Jan 21, 2013 11:23 am ]
Post subject:  Re: 2 stroke mix CR250M 73
I was Midwest regional #1 and National # 4 on it.

All I had to do was match the taper on the rotor to that of the 250 crank, then make a base plate for the stator.

Mud races here in Ohio made me toss the points. Eventually my friend, the now late Dane Leimbach, set me up with a PVL which worked well.

I spent allot of time dialing in my 2fiddy and it worked well, just not well enough as say a mag 2fiddy or a hot penton. They didnt handle near as well as a hoosk and the down pipe just plain sucked. The foot pegs would break off, the frames and aluminum tank would break......

I ran a DG radial head, GEM reed, T&M swingarm, 125 steel tank, jemco pipe and not in the pic was works rear shock.

As soon as I could I built a mag 2fiddy......

Ill BET I still have the set up somewhere in my vast inventory.

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Author:  b-joe [ Tue Jan 22, 2013 10:56 am ]
Post subject:  Re: 2 stroke mix CR250M 73
all my bikes get 1:50 without any problems for many years now.
Author:  ohiomotoxer [ Wed Jan 23, 2013 8:48 pm ]
Post subject:  Re: 2 stroke mix CR250M 73
hahaha try 50:1 on an air cooled engine at Southwick..............
Author:  b-joe [ Thu Jan 24, 2013 6:37 pm ]
Post subject:  Re: 2 stroke mix CR250M 73
that would be no problem.
we also have deep sand tracks here.
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