I have been meaning to ask this for some time but Ron has reminded me.
The front upper sidecar fitting "swan neck". The one which came with my outfit is the lower shorter one, which has been welded up, always a worry with sidecar fittings.
So when the other one appeared at a jumble I thought I had solved this problem, but its longer in the middle section as you can see.
So firstly which one is correct for the big4 please?
Rob
email (option): robmiller11(a)yahoo.co.uk
Thanks Marcel, that's one vote each, hopefully a few more Big4 owners will get their measuring sticks out and we can get to the bottom of this one.
Rob
email (option): robmiller11(a)yahoo.co.uk
Mine is also around 13 inches 33-34cm. The long one at the top. Ron
email (option): ronpier@talk21.com
Yes sorry Rob. I measured mine to include the bottom lug. My straight part is 9 1/2" (241mm)
I also measured the down tubes which are identical (16H & B4) I don't think the down tube length would have any bearing on the side car position as it would only alter the position of the engine for ground clearance. The 16H & B4 forks are also the same length and the fitting of 18" wheels with wider tyres effectively makes the wheel hight's the same at 26".
As we know Norton made several pre war civvy side cars and chassis. There might have been various lengths of swan necks. Maybe your short one has been altered for some reason (you say it has been welded?).
Perhaps Sven could also measure the swan neck on this civvy chassis that I sold him
Ron
email (option): ronpier@talk21.com
Yes Rob it's not a good idea to use my 16H chassis as any form of guide, as I had to make it up as I went along. I actually dropped that rear fitting myself, but I can't remember whether I had to alter the swan neck. It was all done by lining up the Swallow 8 chair by looking at pictures. Lots of trial and error till it looked right.
My B4 is all pretty standard.....I think. Oh the fun of lifting off the chair to work on the left side of the bike!!!
Ron
email (option): ronpier@talk21.com
Here they are;
Regards,
Sven
email (option): snvosselman@gmail.com
Hello Rob.On my big 4 that measurement is only 6 1/2 ".I think the measurement you need is the total length overall as the swan neck length determines the ground clearance at the front of the sidecar chassis.Hope this helps.
email (option): smarwick@iprimus.com.au
Thanks for the input everyone, but I think we still need more.
Sven, in order to see if the big4 chassis had more ground clearance than the 16H combo please could you measure the height of the sidecar wheel spindle centre above the chassis.
Sam, that is a very nice original looking big4 you have there.
Rob
email (option): robmiller11(a)yahoo.co.uk
Hi all, am thousands of miles away from my Biggy's, so no measurements from me for a while, sorry
Cheers,
Lex
ps, will be playing with some enfields in the dessert coming weekend though!
email (option): welbike43@gmail.cxx
Here you go Rob;
Regards,
Sven
email (option): snvosselman@gmail.com
Thanks Sven, I just replied to your email.
It looks like your non driven chassis has a measurement of about 12cm from the top of the chassis rail to the centre of the wheel spindle.
My driven big4 chassis appears to be about 7cm.
The difference of aprox 5cm is close to the difference in length on the front sidecar fittings being discussed.
So here is the theory, Norton gave the big4 more ground clearance than a standard outfit and had to shorten the front upper fitting to compensate.
Apologies to the engineers who use this site for the lack of accuracy but its not easy getting at some of these bits.
Rob
email (option): robmiller11(a)yahoo.co.uk
Rob some more for you to think about. I just measured my chassis from the floor to centre of side tubes. N/S in two paces = about 9" O/S (by bike) in two places = about 8 1/2". So a lean of the chair towards the bike of about 1/2". I set my outfit up with the correct amount of 'lean out' as per the book, and this might account for the lean of the chassis. My swan neck appears to be the same as your long one.
Regarding that plate on Sams outfit. It has been fitted with the banana shaped plate that holds the lower support bar, in a forward position and it looks like someone has had to make a plate to receive the other end of the support bar.
Here is mine.Ron
email (option): ronpier@talk21.com
Rob I think I understand what you are saying. But I set mine up as near as possible to the book with the side car wheel slightly forward of the rear wheel on the bike. You can see this in the picture of my chassis, by the angle of the prop shaft. I created the correct amount of lean out. But I only towed the outfit in by about 1" instead of the ridiculous prescribed 2". (Probably correct for an outfit as heavy carrying three blokes with kit and ammo).
My banana plate is original and I just made the support tube to suit. Ron
email (option): ronpier@talk21.com