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bumper under rider
Posted: Mon Apr 11, 2022 8:59 pm
by new to this
The bumper under rider fits to the underneath of the bumper, but theres a hole in the valance whats that for ?, have i got a bracket missing ?
Thanks Dave
Re: bumper under rider
Posted: Tue Apr 12, 2022 12:10 am
by Carledo
Series 1 cars had the hole in the valance to fit a stabilising bracket to the bottom of the under rider.
Series 2 and later Sprints deleted these supports and turned the under rider into something purely decorative (not that it did that much good WITH the support bracket) At this time the valance holes were also deleted (which also saved money) The early under riders and the stiffener brackets are like hens teeth these days as once they were dropped from production, they didn't make any more and you had to go to the superceded design, same with the front valance once they dropped the holed valance on the line no more were made as spares and you could only get the plain one.
Early under riders have a captive nut in the bottom and can also be distinguished by a thicker rubber pad that protrudes forward of the bumper line in stead of level with it. However the pads are interchangeable so its not definitive.
If you want some brackets and early under riders (though with the later thinner pads) I have some on my FWD that I won't be keeping, the valance is dog rough rotten and i'll be fitting a club GRP one and won't bother remaking the holes. Make me an offer I can't refuse!
Steve
Re: bumper under rider
Posted: Tue Apr 12, 2022 9:57 am
by new to this
Carledo wrote: ↑Tue Apr 12, 2022 12:10 am
Series 1 cars had the hole in the valance to fit a stabilising bracket to the bottom of the under rider.
Series 2 and later Sprints deleted these supports and turned the under rider into something purely decorative (not that it did that much good WITH the support bracket) At this time the valance holes were also deleted (which also saved money) The early under riders and the stiffener brackets are like hens teeth these days as once they were dropped from production, they didn't make any more and you had to go to the superceded design, same with the front valance once they dropped the holed valance on the line no more were made as spares and you could only get the plain one.
Early under riders have a captive nut in the bottom and can also be distinguished by a thicker rubber pad that protrudes forward of the bumper line in stead of level with it. However the pads are interchangeable so its not definitive.
If you want some brackets and early under riders (though with the later thinner pads) I have some on my FWD that I won't be keeping, the valance is dog rough rotten and i'll be fitting a club GRP one and won't bother remaking the holes. Make me an offer I can't refuse!
Steve
Steve
Thanks, got any pictures of what the under rider bracket looks like, and how the bracket attached to the valance ?
thanks Dave
Re: bumper under rider
Posted: Tue Apr 12, 2022 1:49 pm
by xvivalve
The captive nut is on the bracket, not in the under rider; all later under riders retained the hole in the bottom through which the bolt passes. As you’ll see from the attached photo’ some later brackets didn’t have the captive nut and a simple nut, bolt and washers were used instead!
According to Ted's conversations at the factory, the change was to prevent a light nudge on the under rider causing distortion to the inner panels as had been proven to occur; the omission of the holes in the valance would have been a cost in manufacturing as the press tool(s) needed to be amended. Interestingly, I don’t believe the part number for the valance ever changed!
Re: bumper under rider
Posted: Wed Apr 13, 2022 9:35 am
by xvivalve
The later post '76 Dolomite under riders (XKC83/84
https://rimmerbros.com/Item--i-XKC83 ) were side handed, whereas the earlier Dolomite ones (724667
https://rimmerbros.com/Item--i-724667) were not. The fixings between early and late were different, the later ones also bolting through the underside of the bumper blade whereas earlier ones fix only to the bumper iron. The change from deeper rubbers to the shallower ones happened some arbitrary but short time after the under rider type changed
The 1500 FWD and Toledo under riders were a different part altogether 819855 and had a subtly different shape and different fixings again to the bumper/iron; these all had thinner profile rubbers, but a slightly different profile to the later Dolomite:
https://rimmerbros.com/Item--i-819155
Re: bumper under rider
Posted: Tue Apr 26, 2022 8:17 pm
by new to this
A bit of help needed, any one with an early Dolomite with the bigger rubbers on the under riders, could you measure the size of the under rider rubber, id like to try and make a set
Thanks Dave
Re: bumper under rider
Posted: Fri Apr 29, 2022 8:23 am
by xvivalve
It’s an extremely complex compound shape, tapered in various planes. I have some off the car here, but measurements in isolation would not help you and I don’t currently have time to create a CAD model, though I’d suggest it’s a ripe candidate for 3D printing…
I can loan you one if you want to make a mould from it?
Re: bumper under rider
Posted: Fri Apr 29, 2022 8:35 am
by DoloWIGHTY
If you need a bracket I have one you can have FOC.
Re: bumper under rider
Posted: Sun May 01, 2022 3:19 pm
by new to this
xvivalve wrote: ↑Fri Apr 29, 2022 8:23 am
It’s an extremely complex compound shape, tapered in various planes. I have some off the car here, but measurements in isolation would not help you and I don’t currently have time to create a CAD model, though I’d suggest it’s a ripe candidate for 3D printing…
I can loan you one if you want to make a mould from it?
It would be nice to make a mould from it
Thanks Dave