Vintage Dirt Bike Q & A

To the '79 experts out there. As I go through all the parts from my bike, I noticed quite a
few of the rubber pieces are cracked and/or dry rotted (big surprise). I managed to find
replacements for some but I still need the rubber bands that hold the front number plate on.
I see that some of the folks selling repro front number plates for the '73/74s are using what
looks like giant Orings in place of the original strap.

Does anybody know if smaller versions of those Orings are available, and if so, from where?
Or, is everyone using some other method to mount the plate?

Also, when I disassembled my air filter, I found that the filter cage was held in place by the filter
being clamped to the metal base plate. Is this normal or is this some kind of rig?

Any and all help is greatly appreciated.

dogger

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1973 CR250M
1979 CR250R
1993 CR250R
2008 CR500R
2009 CR250R

i use o-rings too
you can get them in all sizes and rubberdiameters.
http://www.simrit.de/files/00001384.pdf

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80 CR250Ra
80 CR250Ra
78 CR250R
80 CR80
82 Bultaco Sherpa 340
78 Bultaco Pursang 250 MK12
76 Bultaco Frontera 370 MK10
76 Bultaco Alpina 250
73 Bultaco Lobito 125 MK6
76 Suzuki RM125A
90 Kawasaki KX250

You need a sewing machine drive belt from your local appliance repair shop...

The way the air filter clamps to the metal base plate is unusual, but correct for this model. The challenge you will have is to find a hose clamp that is long enough to go all the way around, but narrow enough to sit in the groove in the air filter. I ended up with three hose clamps connected end-to-end. I have an OEM clamp, but it is too rare to use.

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Michael Stiles
1979 Honda CR250R Elsinore | 2006 Husqvarna SM510R | 2007 Service Honda CR500R-AF

i tried 3 clamps or a long cablestrap for the airfilter.
this was ok but now i use twinair filters. they have the rubber to the carburator integrated, you dont have to use the cage anymore and it´s easier to install.

_________________
80 CR250Ra
80 CR250Ra
78 CR250R
80 CR80
82 Bultaco Sherpa 340
78 Bultaco Pursang 250 MK12
76 Bultaco Frontera 370 MK10
76 Bultaco Alpina 250
73 Bultaco Lobito 125 MK6
76 Suzuki RM125A
90 Kawasaki KX250

Thanks for the Info, good stuff.

I need to clarify my problem with the airfilter. When I look at the Honda parts diagram, it looks like the filter base plate
and support cage is one piece. Mine is two pieces, a metal base plate and a plastic filter support cage.

Since I am not very good at describing this, as always, I have pictures.

The first pic is the OEM filter base and the ? filter cage. Is this plastic cage the OEM part?
The other pic is the band that holds everything together. I'm assuming it is the correct OEM part.

So I want to know if this is the correct filter cage (I'm guessing not) or do I need to find a replacement if I want to keep
the bike all original.

Thanks.

dogger

_________________
1973 CR250M
1979 CR250R
1993 CR250R
2008 CR500R
2009 CR250R

You're doing fine. The black plastic cage is held by several small metal tabs on the gold metal plate and over time the cage warps and it drops out. No sweat, locate it in place and then the OEM filter slips over the cage/plate. There is a rubber edge to the OEM filter which will line up with the outer edge of the gold plate. Put the band in the groove and cinch it down to make a seal. But before all of this insert the carb boot into the hole in the gold plate and seal it in place with silicone.

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Michael Stiles
1979 Honda CR250R Elsinore | 2006 Husqvarna SM510R | 2007 Service Honda CR500R-AF

Thanks for clearing that up. I found the little tabs you described and you're right about the warpage (as can be seen in the picture). I guess I should be happy the cage is still intact after all these years.

Thanks again.

dogger

_________________
1973 CR250M
1979 CR250R
1993 CR250R
2008 CR500R
2009 CR250R

The holes in the front of the air box where the gold plate attaches will crack...check it out.

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Michael Stiles
1979 Honda CR250R Elsinore | 2006 Husqvarna SM510R | 2007 Service Honda CR500R-AF

i have been meaning to check out this idea myself but instead of using those o-rings to hold stuff together maybe goto your local honda power equipment dealer and ask to see a battery strap from a EU3000 generator. I think it will work very well for holding on the airbox side cover and will hopefulyl work for the number plate and side panels. not sure of the price but i will check it out check it out and post my findings when i get around to getting the item and checking the fit.

...creative!

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Michael Stiles
1979 Honda CR250R Elsinore | 2006 Husqvarna SM510R | 2007 Service Honda CR500R-AF

also gents - at the mine site I work at we use Loctite 401 - it is a special rubber glue which does not melt the rubber. Buy the correct size diameter rubber "hose" - cut to length and glue together. This stuff bonds like you wouldn't believe. I had trouble finding o rings in the size I wanted and now use this stuff.

cheers

Rossco

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1974 Yamaha YZ360B
1977 Suzuki RM370B
1980 Honda CR250RA

so the honda EU3000 generator battery strap does work for holding on the air box side cover. i also imagine it would work for holding the two side panels also. incase anyone is interested the honda part number is 95012-17001 and the price in canada 5.78