OzVMX Forum

Marque Remarks => Yamaha => Topic started by: firko on November 17, 2013, 09:49:04 pm

Title: 1992 YZ250 ignition to DT1/RT1
Post by: firko on November 17, 2013, 09:49:04 pm

I'm soon to receive a '92 YZ250 ignition and I'm wondering if it's possible (and feasible) to fit an RT1/DT1? I had dead stator issues at the Nats and don't want that to happen again so am I on the right track in adapting later ignition or is it just another version of the tried and trued YZ400 or YZ465 ignitions?
                                                                   (http://i1112.photobucket.com/albums/k495/firko2/firko2142/YamahaYZ92IGNITION_zps7d56d6a0.jpg) (http://s1112.photobucket.com/user/firko2/media/firko2142/YamahaYZ92IGNITION_zps7d56d6a0.jpg.html)

Title: Re: 1992 YZ250 ignition to DT1/RT1
Post by: Nathan S on November 17, 2013, 10:07:24 pm

The crank taper will be too larger to fit the YZ flywheel. The later stuff has relatively tiny crank tapers.

If you can deal with that, then it's all win.

Title: Re: 1992 YZ250 ignition to DT1/RT1
Post by: yamaico on November 17, 2013, 10:17:34 pm

Quote from: Nathan S on November 17, 2013, 10:07:24 pm

The crank taper will be too larger to fit the YZ flywheel. The later stuff has relatively tiny crank tapers.

If you can deal with that, then it's all win.

Not too sure about the ignition side of it with regards to advance/retard curves but the hub is only riveted into the flywheel so it would be quite simple to fit an early hub.

Title: Re: 1992 YZ250 ignition to DT1/RT1
Post by: firko on November 17, 2013, 10:32:53 pm

I could get my old lathe jockey mate to machine a larger taper.....I was going to do it with an IT465 ignition as well. Thanks for the tips boys.

Title: Re: 1992 YZ250 ignition to DT1/RT1
Post by: Andrew L on November 17, 2013, 11:41:42 pm

Three mounting slots on the early stuff for back plate only two on later ones

Title: Re: 1992 YZ250 ignition to DT1/RT1
Post by: vandy010 on November 18, 2013, 10:41:18 am

It'll work...
My RT1 uses a YZ490 set up and its all good.
I had to weld some "tabs" onto the stator plste first, then stick thst in the lathe
to get it to fit the RT1 case.
Then you csn measure the distance the flywheel is from the stator plate
and then remachine the taper to suit.
Mine no longer has the keywsy and its never been a problem in the 3~4years
Its been on the bike. Obviously make sure its lapped on well.
Cant remember how many mm BTDC it is but around 3.2 rings a bell.
YZ490 flywheel weighs 1450grams
Cheaper than some of those aftermarket set ups and still Yamaha ;)

Title: Re: 1992 YZ250 ignition to DT1/RT1
Post by: firko on November 18, 2013, 10:46:20 am

Quote

It'll work...
My RT1 uses a YZ490 set up and its all good..........

I remember you telling me that Vandy but is the '92 ignition the same setup (or similar) to the YZ490? I'm following your lead by adapting an IT465 set up for my flat tracker.

Title: Re: 1992 YZ250 ignition to DT1/RT1
Post by: vandy010 on November 19, 2013, 08:27:59 am

Are they the same? Similar?
A 92 YZ250 i'd think would be a pretty good set~up
The task ahead is to get it to physically fit the RT1 motor.
Fit the stator plate first making sure it stays bang on centre,
then you can take measurements from that for machining of the flywheel taper.
Its a bit of mucking around but generally cheaper than a PVL