BMW K bikes (Bricks)


You are not connected. Please login or register

View previous topic View next topic Go down  Message [Page 1 of 1]


1Back to top Go down   A mod for early petrol tanks Empty A mod for early petrol tanks Mon Jul 18, 2016 3:58 pm

sidecar paul

sidecar paul
Life time member
Life time member
While responding to a post from robdiaz44, I looked at the valve that is fitted in the tank for the fuel return line on early K's.

This only affects the tanks with the single bolt fixing at the rear.

Now this valve consists of a spring loaded ball captive in the fitting that screws into the tank and is intended to prevent fuel spillage when the return fuel line is removed.

Unfortunately, they invariably make an awful buzzing noise as the ball lifts and falls against it's seat, so the cure was (is) to prise out the spring retaining plate and remove the spring and the ball. Now, of course, when removing the fuel return hose you have to be very quick with a plug to prevent fuel pouring out or drain the tank beforehand. Both a PITA.

I couldn't find the spring for the picture.

A mod for early petrol tanks Sam_1412

The fuel return line in the later tanks (the ones with the fuel level float) is an alloy tube welded into the tank and the open end is high up in the tank so removing the hose causes no great problem.

Now, if we adopt this approach to the early tanks, all we need to do is solder about 6 inches of 10 mm copper pipe (the hole is already 10 mm dia) to the original fitting after discarding the ball and spring of the valve assembly. 
When the hose is subsequently removed you just need to catch the egg-cupful of fuel that remains in the copper pipe.

A mod for early petrol tanks Sam_1413

As I have quick connects on my fuel lines I don't need this mod, but the idea may be of use to someone.

Paul.


__________________________________________________
'84 K100RS (0014643) (owned since '85), 86 K100RS (0018891) with Martello sidecar (built as an outfit in '88),
'51 Vincent (since '67),'72 Montesa Cota (from new), '87 Honda RS125R NF4 (bought 2015) 
....No CARS never ever!
    

2Back to top Go down   A mod for early petrol tanks Empty Re: A mod for early petrol tanks Tue Jul 19, 2016 5:30 pm

sidecar paul

sidecar paul
Life time member
Life time member
I used CPC fuel line connectors and posted it here:-

https://www.k100-forum.com/t3308-fuel-line-connectors

Bear in mind that the plastic male connector is the weak link and can break, but the plastic female connector does fit with the stronger brass male connector, should cost be a consideration.

Paul.


__________________________________________________
'84 K100RS (0014643) (owned since '85), 86 K100RS (0018891) with Martello sidecar (built as an outfit in '88),
'51 Vincent (since '67),'72 Montesa Cota (from new), '87 Honda RS125R NF4 (bought 2015) 
....No CARS never ever!
    

View previous topic View next topic Back to top  Message [Page 1 of 1]

Permissions in this forum:
You cannot reply to topics in this forum