Girder fork top spring mount

[alan.moore]

Getting to know my new WNG I noticed the Girder spring top mount appears to have a separate 'top hat' where the mount fits into the upper girder yoke. My 1939 does not have this fitting. Looking at the 1941 WNG parts list and the VH list the mount is shown in both cases as 4612-32, no mention of this extra bit.
So.... in the first of many questions which I feel sure will follow, is this part an original WNG addition?

Top mount WNG

Top mount VH

Cheers
Alan

[nevhunter]

Any kind of spacer there would affect the strength of the fitting D10/39 as it's tapered and fit's into D10/104. No W/NG's I've seen have such a spacer. It may have been fitted with a longer bolt to compensate for spring sag. That would subject the bolt to too much strain as you've lost the function if the papered fit in locating it. Nev

[alan.moore]

I haven't dismantled it but removed the bolt and the additional spacer looks as though its tapered at both ends, at the bottom to accept the original taper (D10/39) and at the top to fit into the top yoke (D10/104). It is a machined piece just for this purpose. It gives an increase of 1/2 inch.

has anyone got a parts book later than 1941, maybe its a later addition?

Cheers
Alan

[simon.holyfield]

I've got a few parts books Alan. I'm working away from home for the next couple of days but I'll be back at the end of the week.

[nevhunter]

It's still weaker The additional spacer piece has a smaller outer dia than the top fitting has. I've never seen one fitted (but that doesn't mean it's not a part.) Is the spring the normal length?. If you are sure the lengthened bolt is high tensile or something decent and the tapers fit well, it's probably OK Nev

[ian.scott]

I had to fit a similar spacer to my VH as the front mudguard continually crashed into the girder fork bridge casting in spite of fitting a new OS spring. This was initially when used in trials trim but since our roads have deteriorated into their current state it is needed on the road as well.

Ian

[alan.moore]

Thanks for that Ian. Is the spacer an Ariel part or did you make one yourself?

Cheers
Alan

[ian.scott]

I made it myself. Originally it was only roughly made to try out but as it solved the problem so I and tidied it up and refitted it.

Ian

[simon.holyfield]

I've got a few parts books Alan. I'm working away from home for the next couple of days but I'll be back at the end of the week.

Nothing in the parts books...

[paul.jameson]

This is definitely a new one for me. There are 2 versions of the girder spring top mount but you have the same type on both your bikes which has a flat top surface above the fork spring. The earlier type has a more conical surface. It took me years to spot the difference between the two. That difference is the angle of the "slots" which take the top of the spring. The early type has the slots tapered the same way as the spring coils. The later type has the slots tapered the opposite way, presumably to grip the coils of the spring better. Clearly this was seen as a problem since the drawing for the spring instructs you to fit the spring to the top mounting before enamelling.

Given this evidence of problems and developments in this area I can only conclude that your extra fitting is another attempt to solve the problem.

The problem, in my experience, is that the top mounting comes loose in the taper fitting in the top of the fork girder. No way could I keep the one on my RH tight so I used to run it slack which it survived happily for many years. Then the threads stripped in the top mounting so I had to go up a thread size (but the same hex size on the bolt head for appearance sake.) I still run it fairly loose and it gives no problems. Despite many bumps ridden over, the spring top mount has yet to become detached and if I haven't done it by now, I don't think it is going to happen. So perhaps the problem is one which causes fairly instant concern, but in the end, doesn't matter.