Navigation

You are here: Home / Messages / Heavy Twins / slimline tank front mountings

slimline tank front mountings

Up to Heavy Twins

slimline tank front mountings

Posted by robert_tuck at June 28. 2017

Can't seem to find a decent  description of what should be. I have a fair assortment of fittings that have come from our suppliers ,none of which seem to want to work together as they should. My understanding is that the rubbers should compress enough to grip the tank and not allow rattles but the bolts should tighten to a positive stop  so that they do not vibrate loose as the tank moves on the rubber. No one seems to market these as a set  (which one hopes has been tested to work) so we finish up with a random selection of bits with no measurements.

Re: slimline tank front mountings

Posted by David Cooper at June 28. 2017

About 3 years ago I bought a set of four for my prewar 16H and they are identical to the pair at the front of the Dommie tank.  One design detail Norton never changed for well over 35 years!

As you say - shouldered  bolts so they are fully tightened hard up.  Top hat rubber washers above and below the tank plate and meeting each other in the hole in the tank plate.  Steel disc washer with turned-up edges above and below the top hat rubbers to transfer the squeeze from the bolts.

Aren't they listed by Andover Norton?  I suspect that's where mine came from.

Regards

David

Re: slimline tank front mountings

Posted by robert_tuck at June 28. 2017

Interesting David, my sets comprise of 12 items  ,6 each side,  A part threaded bolt a washer a steel cup a top hat rubber a plain rubber washer and a large steel washer . Nothing like yours!, can't find a picture or description . RGM at least give a detailed description of a top hat rubber ,but thats it.Andover has nothing, Norville has no worthwhile decription or pictures .No one has a set.

Re: slimline tank front mountings

Posted by David Cooper at June 28. 2017

That sounds OK. I can't remember if I have one flat and one cup but no matter. I'd better go and have a look rather than rely on possibly faulty memory. I'll try and take a photo later.

Re: slimline tank front mountings

Posted by robert_tuck at June 28. 2017

Perhaps the earlier bikes have a picture or description, Be nice to have a few more opinions .I have a Norton parts list!, the front fixings amount to 10 total items, Bolt, washer for bolt, steel cup ,rubber washer , rubber washer. The rubber washers have no description and there are 2 types so at least one is a top hat. no steel washers above the frame.

Re: slimline tank front mountings

Posted by David Cooper at June 28. 2017

Pic of 16H.

Attachments

Re: slimline tank front mountings

Posted by Neil Wyatt at June 28. 2017

The 16H picture looks correct, as long as the top rubber washer of a top hat design goes through the tank mount to make contact with the bottom rubber washer that sits in the cup.

I bought 2 of each for my 99 the year before last from RGM. The cup and shouldered bolt with very long hexagon (AF) in Stainless.

Re: slimline tank front mountings

Posted by robert_tuck at June 28. 2017

Hi David, According to the Norton parts list you are missing the washer between bolt and cup, this would affect the degree the rubber tightens a little. I suspect if both rubbers are top hat design then the upper one will be larger diameter or thicker than the lower one as its a different part number.I have tried your set up and it appears better than mine but the thread does not lock up.

Re: slimline tank front mountings

Posted by David Cooper at June 28. 2017
The order on mine for top to bottom is: threaded plate welded to tank circular steel washer (to provide a circular bearing surface for the next item) circular rubber (I'd have to take it off to see if it has top hat arrangement) lug welded to frame circular rubber (again I don't remember if this also has a top hat or the other one does - or both) large round cup washer bolt head The bolt is shouldered and long enough for the shoulder to be tight on the tank threaded plate, whilst short enough to give the two rubbers a good squeeze. I don't think this had another washer between the cup and bolt head but if that is what the parts list says then the PO missed it out before the early 1960's when it was last on the road before I took it on. Unless the washer at the top belongs at the bottom. But then the tank lug would not provide a full size circular surface for the top rubber. I've no idea why there is only one cup washer. The top hat goes through the frame lug (not the tank plate - that would not work) to meet the other rubber below (I don't see any reason for which type of rubber goes on top as long as at least one top hat fills the hole in the frame lug). So the top hat insulates all the steelwork from the frame lug with the bolt fully tight. The Dommie is the same but it's less accessible and harder to photograph. I had no idea that any sizes differed. I'm pretty sure it's all interchangeable but Norton seem to have take fiendish delight in making unnecessary changes! I can measure it tonight if you want to work out why the thread won't lock up solid. (ps - my speedo cable is looking a bit rougher than I expected! Needs to be tied better by the looks of things... the sidecar lug seems to be attacking it...)

Re: slimline tank front mountings

Posted by Jonathan Soons at June 28. 2017

I used the shouldered bolts but I bought a lot of big rubber washers and experimented til the tank floated above the frame on a rubber cushion. I have rubber washers above and below the frame brackets.

Re: slimline tank front mountings

Posted by anna jeannette Dixon at June 28. 2017
Previously robert_tuck wrote:

Interesting David, my sets comprise of 12 items  ,6 each side,  A part threaded bolt a washer a steel cup a top hat rubber a plain rubber washer and a large steel washer . Nothing like yours!, can't find a picture or description . RGM at least give a detailed description of a top hat rubber ,but thats it.Andover has nothing, Norvil has no worthwhile decription or pictures .No one has a set.

 

Re: slimline tank front mountings

Posted by robert_tuck at June 28. 2017

Hi David,I also have had the large steel washers against the tank for years but according to the Bracebridge St  parts list they should not be there,and it seems to work without them. Try again Anna, I'm all ears.

Re: slimline tank front mountings

Posted by michael_jobson at June 28. 2017

Read the parts list. Look at the exploded drawings. Then contact Norvil or simply read their on line parts list. All of the parts are listed and priced. It is a very simple arrangement and the discussions on here are making the whole arrangement sound complex when it is not.

Re: slimline tank front mountings

Posted by David Cooper at June 29. 2017

Tha only picture I have found us in the WD Norton manual. Page 1o has a good picture and is identical to mine. No flat washer at the bottom.

My Dommie spares list is totally confusing. Two bolts at different sizes and 2 cup washers.

Re: slimline tank front mountings

Posted by robert_tuck at June 29. 2017

Previously michael_jobson wrote:

Read the parts list. Look at the exploded drawings. Then contact Norvil or simply read their on line parts list. All of the parts are listed and priced. It is a very simple arrangement and the discussions on here are making the whole arrangement sound complex when it is not.

If it was that easy we would not be asking, which exploded drg?,where?, If it was well detailed then the suppliers would know what to supply instead of the random collection of completely useless parts they sent me last time.

Re: slimline tank front mountings

Posted by michael_sullivan at June 30. 2017

Robert:  According to the parts list I have for my 1961 Model 50 the petrol tank fittings are shown to be:

2ea 16237 Frame mounting rubber for petrol tanl

2ea 22081 Frame fixing bolts

2ea 22082 Rubber washers for fixing bolts, top

2ea E6743 Rubber washers for fixing bolts, bottom

2ea E6742 Steel cups for rubber washers

2ea 10914 Washers (steel) for steel cups

If I remember correctly. the bottom rubber washer has a step in it that fits inside the hole in the frame tab. Or is it the other way around?

Mike

Re: slimline tank front mountings

Posted by robert_tuck at June 30. 2017

5 items per mounting is what I understand ,but as they are not pictured or dimensionly described  even the suppliers staff picking these for orders  get it wrong ,with the result that the bolts don't lock up and work loose to fall out or worse they don't even have holes in for the bolts.  The stepped washer goes in the bottom  and sits in the cup. I stick the plain thick top washer to the frame with UHU or similar contact adhesive, Compared to some other makes Norton parts are very poorly drawn or described although RGM is making an effort.I also think they could be sold as a "set" which would also make the suppliers more responsible for them to be  "Fit for purpose ".

Re: slimline tank front mountings

Posted by john_evans1 at June 30. 2017

I could not find them either. I just used tbick rubbers which once acted as bump stops for the rear shocks on a merc..others will also fit!  The tank dies nit move. No vibes and it looks original at a casual glance.

Re: slimline tank front mountings

Posted by Fritz Wettstein at July 01. 2017

I've found a picture on Norvil's web site: http://www.norvilmotorcycle.co.uk/techtalk32.htm

Fritz

PS: Couldn't remove the attachment Frown

Attachments

Re: slimline tank front mountings

Posted by robert_tuck at July 01. 2017

Well done Fritz,  I never found those details.  Still not definative though as the diagram depicts the flat washer as being very thin (its not) and the photo (which should be more accurate) shows the stepped washer about twice as thick as it should be!, This thick/thin business is important as if its not correct those bikes that actually get ridden will lose the bolts sooner or later if the assembly does not fully lock up. Alright for trailer queens though.

Re: slimline tank front mountings

Posted by philip_ham at July 02. 2017

I know this isn't about Heavy Twins as the original article but the thread seems to have strayed away to include 16H.  The attached photo shows the arrangement of the tank fixings for my 1955 ES2, which was used for many years.

This is very similar to my 1969 Mercury, although the bolt head changed from Whitworth to AF spanner sizes.  The top hat washer sits on top of the frame brackets and the plain rubber washer below; this ensures that the bolt and tank are totally isolated from the frame.  I've never seen or used the metal packing washer (A2/275) mentioned in the parts list, but all has worked well since buying the ES2 in 1970!

I recently purchased the stepped bolt (A2/277) and the steel washer cups (A2/279) from the NOC spares scheme.  I think I bought the rubber washers from Jeff Hunter Engineering from the VMCC autojumble at the Bath and West Showground.

Philip Ham.

Attachments

Re: slimline tank front mountings

Posted by robert_tuck at July 03. 2017

Thanks Phil and others who have replied, I think I will try that,although I dont want AF hexagons on my bike  so will try to stick with the old rusty bolts. I will probably have to cut down the top hat rubbers to get to a lock up situation and it would make sense to include a thin large steel washer against the tank though it would have to be stuck to the rubber for ease of fitting. Shame no one supplies a "set" of parts that can be trusted to work.Perhaps they know the parts are a missmatch!!.

Re: slimline tank front mountings

Posted by philip_ham at July 03. 2017

Previously robert_tuck wrote:

Thanks Phil and others who have replied, I think I will try that,although I dont want AF hexagons on my bike  so will try to stick with the old rusty bolts. I will probably have to cut down the top hat rubbers to get to a lock up situation and it would make sense to include a thin large steel washer against the tank though it would have to be stuck to the rubber for ease of fitting. Shame no one supplies a "set" of parts that can be trusted to work.Perhaps they know the parts are a missmatch!!.

Robert,

The stepped bolt in my photo is NOS from NOC spares and is 5/16" WW.

Phil.

Re: slimline tank front mountings

Posted by Fritz Wettstein at July 03. 2017

I've changed the setup. I' use a screw which goes to the thread in the Tank. Less fiddeling arround with the rubbers and steel cups. No more risk to damage the coating on the tank while trying to hit the holes.

Fritz

Edit:

My writing above is completley rubish.Innocent I've changed to bolts «loctited" in the tank, instead of screws.

Re: slimline tank front mountings

Posted by michael_jobson at July 12. 2017

I don't read the NOC messages an a daily basis and have just returned to this thread to see how it ended. The initial query asked about how the front mounting was made up on a Slimline tank. After some discussion the schematic, and it only that and is not to scale, and its accompanying photo were found on the Norvil website. these clearly show exactly how the Norton mounts were designed and fitted, and from my own experience it works exceptionally well.

Then having had that information the original poster became critical of suppliers who did not supply a "kit of parts" for this arrangement. Which makes me wonder just how hard some people actually look. I know that in the modern age people generally expect to have instant solutions presented to them and so they just do not research things in depth. The advent of social media in all its forms encourages this I am afraid. So did RT actually look closely into the availability of a "kit of parts" for his Slimline tank? I know not, but I do know that if he and others had looked at the Norvil site they would see a heading at the top of the home page which lists "Kits". Item 28 in that list is headed "Petrol Tank, and in this list are complete kits of parts for the fixing of tanks for Heavyweight Twins, Singles and Commandos. It lists a kit 067384: Kit: Petrol Tank: Slimline Featherbed: Including bolts.

Like I said earlier if the tank is fitted as shown in the schematic and the photo it will be secure. If you are concerned about losing a fixing bolt in use then simply Loctite them or fit locking wire. The correct bolt is stepped and when tightened it compresses the rubber the required amount to allow the rubbers to operate as anti vibration mounts. The tank itself was built with a reinforced insert into which the bolts fit so there is absolutely no need to fit a washer between the bolt shoulder and the bottom of the tank. HTH

 

Powered by Ploneboard
Upcoming Events
Tay Valley Branch Camping Weekend - Applecross Jul 28, 2017 - Jul 29, 2017
CRMC Track Parade - Donington Classic Festival - 3 days Aug 04, 2017 - Aug 06, 2017 — Donington Park, Castle Donington, Derby DE74 2RP
Yorkshire Branch at the Hebden Bridge Vintage Weekend Aug 05, 2017 - Aug 06, 2017 — Calder Holmes Park, Hebden Bridge West Yorkshire, HX7 8EE.
Brittania Rally - Denmark Aug 18, 2017 - Aug 20, 2017 — Jolly Roger Mc, Nørre Langgade, 8840 Rødkærsbro, Denmark
2017 International Rally Aug 24, 2017 - Aug 28, 2017 — Open Huis, Ieperstraat 157 - 8840 Staden, Belgium
Upcoming events…
This is Brio Diazo Plone Theme