Fork brace and fiberglass

Before I get to my question I'll introduce myself quickly. My name is Ben, I'm 25 and I've been hanging around here for almost a year now, doing much more reading than posting. Without knowing anything about Norton motorcycles, other than being super cool, I got a good deal on a '74 850 last fall that I couldn't pass up. So here I am almost a year later and I'm just starting to collect parts. Now, you can believe that I've been doing my homework and I've already got all new bearings and bushings to make the bike safe. I also got it running a few days after I brought it home.

So my question is: I have a JPN fiberglass front fender. I know that on most other bikes a steel front fender acts as a fork brace. Am I going to need a fork brace with a fiberglass fender? It sure seems it to me but I haven't had any luck finding anything that fits a Norton.

I realize this part of the rebuild is way in the future and I probably have much more to think about, but I'm not sure when I'll actually be able to get started on this project and I just want to keep my eyes open for parts that might not come up that often.

This is just the first question of many, so I'll thank everyone in advance.

Ben

Ben,

Do you have any machinist skills? If so, I predict you'll be quite valuable to the Norton community. Even not having such you are a welcome addition.

As for the fork brace, I only have experience with steel fenders. I do recall my 69 Commando, back in 71 when I first acquired it, had no front fender . I don't recall any drastic effects. Try it, you can always add a fork brace.

Good luck to you. Hope to hear from you, often.

Hi Brly
Welcome to the forum
I know Norman Hyde made aluminium fork braces once upon a time for Commandos but I don't think they are produced anymore. Try Evil bay...
This item sometimes shows up there. It’s a bit of a pain to install but once set-up correctly they work.
CNN

I believe that a standard fender does have a strengthening effect, however at the speeds and performance parameters that most people ride within I doubt it would make a significant difference. I have found that a Harley Sportster steel front fender (I bought an aftermarket one on E-bay for $35 brand new) with the mountings suitably redrilled makes a good compromise between the look of a less bulky unit and the strength of the original.

Welcome to the coolest never ending hobby horse club around Ben.
I can tell you for a flat fact the steel "mud guard" does nil as a fork brace.
You have to get pretty wild-to dangerous to get into states that Roadholders twist and spring back. Can get like rubber bands between grips and forks, road twistes forks one way while pilot is turning another for combined spring back that is un-fun exciting. But again I repeat - you'd better be a hot shot dirt rider or similar to be able to enter fork twist up states and recover un-harmed by the lesion.

What Commando's are way more famous for is called 'Hinged Handling'. Its something every bike in the world [but two of a kind Commandos] can experience, just the rubber mounted Cdo gets that upset at lesser loads than more rigid moderns. I'd rather ride out the hinged Commando than hot shot modern as Cdo happen with more warning and at rates humans can handle, while modern onset hit a lot harder at higher frequency and way more suddenly.
850's stem angle is less acute than 750 so not as quick and handy as 750 but still can drive sports bikes nutz in the tight and twisties. The real danger of Cdo handling hits in long held fast sweepers where there is time for the various resonances to build up. Forks will still twist up but way less with the brace which also raises the rebound freqency up higher than affects line holding or traction.

The only fork brace I can recommend is sold by RGM in UK. Costs like $250+shipping. I've collected reports of the Hyde brace being rather frail. RGM's is robust rigid and also extends the over lap support of the forks at full extension.
Order their hard copy catalog, to view when alone eh. http://www.rgmmotors.co.uk/



Brace help can definitely be felt off road too, maybe even more than on tarmac.

Hyde brace for vintage wimpy style.