CR250M - Ign black box

[Jumbo J]

I'm replacing the points with a CR125 ignition. To any of you guys that have done this type of conversion before where is the best place to mount the black box. There's not a lot of room under the tank or the seat for that matter. Around the head-stem down tube area perhaps, like the RM's / PE's ?

[OverTheHill]

just remember the 125 cdi will [should] have more advance at low revs after it's started but [might] retard off beyond the 250 set timing figure & knock the top end power so may need to give it more advance on the back plate to overcome this. They were a good old points system & sold a new one recently i'd had for years. Good cdi set up on the 125 too though. Rode both 'new' back in the day & loved that 125 on rough tracks--just keep it nailed. Just google 'Honda No1 under the sun' & this popped up. Pretty pathetic by modern standards but good for a laugh. Me on the Cr250M Elsinore. Took us a few days stop/start [weather] to make this add. Uhh, can't watch it any more lol.

http://www.ngataonga.org.nz/catalogues/moving-image-catalogue/media/honda-125cc-motorcycle-no1-under-the-sun-c1663?option=com_events&task=view_detail&agid=2020

[Jumbo J]

just remember the 125 cdi will [should] have more advance at low revs after it's started but [might] retard off beyond the 250 set timing figure & knock the top end power so may need to give it more advance on the back plate to overcome this. They were a good old points system & sold a new one recently i'd had for years. Good cdi set up on the 125 too though. Rode both 'new' back in the day & loved that 125 on rough tracks--just keep it nailed. Just google 'Honda No1 under the sun' & this popped up. Pretty pathetic by modern standards but good for a laugh. Me on the Cr250M Elsinore. Took us a few days stop/start [weather] to make this add. Uhh, can't watch it any more lol.

http://www.ngataonga.org.nz/catalogues/moving-image-catalogue/media/honda-125cc-motorcycle-no1-under-the-sun-c1663?option=com_events&task=view_detail&agid=2020

Thanks.
I used to drive beach buggies on those sand dunes in the 70's. Drove up from Otaki beach.  Waiorongomai river crossing was always a challenge. Have a photo around somewhere of the flathead with duals on the back 

[jimg1au]

my yamaha cdi box is mounted under the tank behind steering head on my 1973 cr250m

[bigk]

Plenty of room under the tank for CR125M CDI, just make some nice brackets, done it many times.
K