Bonnet Fasteners

Chrispy
Posts: 14
Joined: Tue Feb 26, 2019 10:17 pm
Location: Isle of Thanet

Bonnet Fasteners

Post by Chrispy » Thu Mar 05, 2020 9:56 am

Who can advise good alternative to the long winded screws holding bonnet on?

Dzus would probably look best but seem problematic to install. There appear to be loads of alternatives available, so what have owners fitted and which ones work best?

westendguzzi
Posts: 326
Joined: Tue Sep 25, 2018 7:30 pm
Location: Huntingdonshire

Re: Bonnet Fasteners

Post by westendguzzi » Thu Mar 05, 2020 10:52 am

I still have the standard M6 socket head csk set screws.
Screw driver handled allen key for reasonably quick access.
The front 2 have had an extra threaded piece bonded on as the thread had worn.
The rear 2 now have extra loose nuts (with a short handle welded to them) to lock the crews on. Two handed job there.
I used over-centre clamps on the Pembleton but don’t think they would look so good on the T4, unless you could mount them inside.
As the under-bonnet area is used for spares/tools stowage, the set screws seem reasonably secure. Would probably be even better with torx heads.
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JFerg
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Joined: Sun Sep 30, 2018 10:02 pm
Location: Melbourne, Oz

Re: Bonnet Fasteners

Post by JFerg » Fri Mar 06, 2020 2:02 am

On my early Type 1 I have studs in the bonnet which locate into the corresponding holes in the body. This simplifies fitting the bonnet. At the front I have hand knobs, so it's a one-handed reach to undo or re-fit them. Works well. At the rear I have hex nuts, but they're just under the dash and at least you can see 'em.

I use dzus fasteners on a bike fairing. They are very good, but you need to get directly behind them and apply pressure down, which would be tricky under a Triking bonnet.

Image

cheers,

JFerg
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Chrispy
Posts: 14
Joined: Tue Feb 26, 2019 10:17 pm
Location: Isle of Thanet

Re: Bonnet Fasteners

Post by Chrispy » Sat Mar 07, 2020 11:53 am

Thanks both for replies. I should add that I want stainless steel fasteners and not bothered if showing as long as quality is there on show.

The over centre clamp idea seems simplest but the ones I've seen on web seem to pull on catch mounted in same plane as lever. On the Triking the catch would be 90deg. to the lever and not sure designed to clamp properly that way! They would possibly also have the advantage of adjustability.

Shall keep on looking.

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frederick
Posts: 51
Joined: Mon Oct 01, 2018 8:05 pm
Location: san jose

Re: Bonnet Fasteners

Post by frederick » Sat Mar 07, 2020 7:12 pm

For a vintage look I’m using spring loaded hold downs...two bonnet rear, two deck lid top. Bonnet front and deck bottom I’m planning long threaded wing screws.
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EricStarmer
Posts: 227
Joined: Fri Sep 28, 2018 3:51 pm
Location: USA

Re: Bonnet Fasteners

Post by EricStarmer » Sun Mar 08, 2020 9:28 pm

I didn't like the idea of the screws holding the bonnet down either, so at one point I came up with a complicated system whereby the bonnet opened up, rather than having to take it completely off, and it didn't involve screws at the rear, just metal tabs that slid under the fibreglass where the wipers are. The problem with this turned out to be that without the screws at the rear, the bonnet wouldn't stay flush at the sides without something physically forcing the sides in . Now I've gone the usual screws at the back, but at the front I made a bracket that attaches to the oil breather, and a bracket inside the bonnet nose, so that the front can be quickly undone by unscrewing a knob.
Having recently had various minor problems with blown fuses and suchlike, where I've had to remove the bonnet and find somewhere to put it without chipping paint off, I'm thinking of going back to the cantilever system, but also with the screws at the rear, although maybe some more metal tabs will be enough to keep the sides of the bonnet in at the back- we'll see.......
Attachments
Bonnet 2.jpg
Bonnet 1.jpg

EricStarmer
Posts: 227
Joined: Fri Sep 28, 2018 3:51 pm
Location: USA

Re: Bonnet Fasteners

Post by EricStarmer » Sun Mar 08, 2020 9:29 pm

A couple more photos
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Bonnet 4.jpg
Bonnet 3.jpg

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frederick
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Location: san jose

Re: Bonnet Fasteners

Post by frederick » Mon Mar 09, 2020 2:28 am

Slick! Solves where to put the “bonnet” when you take it off. How’s access to the motor’s fiddly bits?

westendguzzi
Posts: 326
Joined: Tue Sep 25, 2018 7:30 pm
Location: Huntingdonshire

Re: Bonnet Fasteners

Post by westendguzzi » Mon Mar 09, 2020 10:41 am

If using the over-centre clip or the spring hold-down, I think vertically orientated dowels moulded into the body with moulded in metal 'holes' in the bonnet would keep the 2 planes aligned.

EricStarmer
Posts: 227
Joined: Fri Sep 28, 2018 3:51 pm
Location: USA

Re: Bonnet Fasteners

Post by EricStarmer » Mon Mar 09, 2020 3:47 pm

Frederick - access to the engine is good, although so far, fortunately I've had zero problems with it (I've put 2500 miles on a donor that had 21000 miles )

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