OzVMX Forum

Clubroom => Tech Talk => Topic started by: HL500 on April 17, 2015, 06:55:05 pm

Title: Honda 1980 CR250 CDI
Post by: HL500 on April 17, 2015, 06:55:05 pm

Hi, an anyone tell me if the 79 CR250 "D or E or F" labelled CDI can be used with a 1980 alternator.  I noticed there is only one choice alternator for the 1980 model hence not labelled.

I looked up a part number for the 1980 CDI but coouldn't find one in the parts book so I am assuming earlier models fit?

While on the subject, is one better than the other in the 1979 range and why were there different versions?

Title: Re: Honda 1980 CR250 CDI
Post by: FourstrokeForever on April 20, 2015, 10:47:31 pm

I'd be very interested to know the differences myself. Any body got a heads up on what the differences between the 78' and 79' CR250RZ CDI's is? Which one is the ducks guts? "D" "E" or "F"?

Title: Re: Honda 1980 CR250 CDI
Post by: Rossvickicampbell on April 20, 2015, 11:04:43 pm

Story has it the 78 had an "A" CDI which does not fit the 79 but "B" through "F" are interchangeable between bikes.  Can't remember why but the "E" ignition was the choice of them all.  As long as all parts are the same (rotor etc)  ie "A", "B", then all should be fine.

Title: Re: Honda 1980 CR250 CDI
Post by: FourstrokeForever on April 21, 2015, 09:56:57 am

Thanks Ross. I'm going to check mine out to see what ignition I have.

Title: Re: Honda 1980 CR250 CDI
Post by: marshallmech on April 21, 2015, 06:58:34 pm

Have a good look at the alignment hole on each different letter cover. 
The internal stator is the same for 78/79 not sure about 80

Title: Re: Honda 1980 CR250 CDI
Post by: HL500 on April 22, 2015, 10:53:48 am

Thanks guys.  Turns out I have the E version amongst my collection.  But I noticed on the different stators there is a serial number stamped and they differ only by the letters. Could the stators could also be matched. 

Title: Re: Honda 1980 CR250 CDI
Post by: Rossvickicampbell on April 22, 2015, 12:04:43 pm

I think all parts have to match - ie all "E" or all ""B" etc.

Title: Re: Honda 1980 CR250 CDI
Post by: FourstrokeForever on April 23, 2015, 07:26:28 am

I believe all ignition parts have to match otherwise engine damage will occur

Title: Re: Honda 1980 CR250 CDI
Post by: bigk on April 23, 2015, 09:56:39 am

If they don't match, the bikes run like puss.
K

Title: Re: Honda 1980 CR250 CDI
Post by: marshallmech on April 23, 2015, 09:26:32 pm

I have found the internals to b the same the pin location matches the timing for the Different letter CDI just what i have found

Title: Re: Honda 1980 CR250 CDI
Post by: HL500 on April 24, 2015, 02:53:24 pm

Thanks for your comments guys. Its a lot clearer now and greatly appreciated. But I am still interested in knowing why Honda saw it necessary to come up with what I believe are 5 versions plus a different one for the 1980 model.

Title: Re: Honda 1980 CR250 CDI
Post by: FourstrokeForever on April 24, 2015, 05:36:55 pm

Quote from: HL500 on April 24, 2015, 02:53:24 pm

Thanks for your comments guys. Its a lot clearer now and greatly appreciated. But I am still interested in knowing why Honda saw it necessary to come up with what I believe are 5 versions plus a different one for the 1980 model.

I guess they thought it was the easiest and cheapest way to tune the factory race bikes for different conditions.

Title: Re: Honda 1980 CR250 CDI
Post by: Lozza on April 24, 2015, 06:41:24 pm

Most times they were saved up for factory teams and selected riders. I have a few old Kawasaki bulletins that have 6 different flywheels for KX250's with descriptions on what flywheel to use on what type of track