RD Petcocks (125 - 350)

[sav0r]

So the petock on my wife's RD125 is bad. I've been switching the one on my 350 back and fourth between our two bikes over the years.

I'd like to stop that.

I see economy sells a nice reproduction, but for $80+ shipping, ouch.

I'm thinking about machining a bolt on bit that will adapt a Honda pipe thread petcock. Clearance might be a

Has anybody done this? I'd rather not braze a bung on, but since her tank is so-so, I am considering it.

Petcock I am thinking about adapting:

https://www.ebay.com/itm/Fuel-Valve-Petcock-Honda-CL175-CB350-CL350-SL350-CB360-CL360-CB450-CL450/362585186045?fits=Model%3ACB350%7CMake%3AHonda&hash=item546bc2defd:g:TAQAAOSwoG1ciq84:sc:USPSFirstClass!15214!US!-1&frcectupt=true

[m in sc]

that 16mm thread is a pain in the ass, however, you can make an adapter plate. m16x1.5 bolt, drill it out,  braze/weld it onto a steel plate, drill 2 mounting holes, cut a gasket, and use 2 stat-o-seals to seal the bolts on the plate.  or use a 1/8" npt petcock and make an aluminum adapter plate.

[suey1958]

Not trying to hijack your thread but I am also in need of the same petcock  for my project.
I am wondering why some petcocks (on e bay)  that are listed as fitting rd350's are $7.50 w/ free shipping but are not the same. Why are the ones that we need are 80 and the others are just $7.50 ? Just wondering?

[sav0r]

That flanged $7.50 petock doesn't fit an RD350 tank. It's also pretty long, so adding an adapter makes it pretty cumbersome. I know, because I have one and did just that. It basically does't fit, even on the 125.

I was thinking about machining a 16mm adapter plates out of aluminum. Probably just cut the threads with a thread mill. Good to know it's m16 by 1.5. I can see how many trillions of dollars a single point thread mill is going to cost.

[bracket maker]

That flanged $7.50 petock doesn't fit an RD350 tank. It's also pretty long, so adding an adapter makes it pretty cumbersome. I know, because I have one and did just that. It basically does't fit, even on the 125.

I've had some bad experiences with cheap petcocks. you get what you pay for. been winding up changing them every season. nothing worse than a leaky petcock. needed 3 for my cb in 2 years. one of them was bad from first day.

[quocle603]

The cheap aftermarket ones have very poor quality gaskets and the gasoline will eat right through them.