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   Collapsing Fuel Return Line Empty Collapsing Fuel Return Line Fri Feb 09, 2018 4:42 pm

MartinW

MartinW
Life time member
Life time member
A few week ago I suffered intermittent bad running, this was due to the fuel return line collapsing where it bends at 90 Deg to enter back into the tank. I tried a few solutions but it eventually collapsed again, the collapse mainly occurred on really hot days in traffic around 39 C.  I tried at least 5 different ways of routing. I removed the fuel cooler which was causing one of the problems due to the fuel line  needing rerouting. I trimmed back the line about 1.5" to do away with the point where it was collapsing. All these measures worked from anywhere from a couple of days to a couple of weeks. I have it cured at the moment with a rather ugly solution. I extended the hose by about 10" with a barb joiner ran the hose up through the steering head and looped it around and back into the tank. All the bends are now large with no possibility of kinking, and the K75s fairing covers it all up. However I went in search of springs to go over or in the fuel hose in order to solve the problem,and make it a little bit neater. A guy I deal with at Pirtek put me onto these Unicoil which are a modern interpretation o the old spring trick. Autobarn has them in various sizes $20.00 Au or Ebay has the identical ones for $8.00 Au plus $8.00 Au postage. https://www.ebay.com.au/itm/5-16-Stainless-steel-UNICOIL-Hose-coil-suit-hose-OD-14-16mm/152678074659? 
When it arrives I'll post the results, although I can't see there being any problems with it at this stage.
Regards Martin.
Collapsing Fuel Return Line Unicoi10

    

2Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Fri Feb 09, 2018 4:59 pm

Inge K.

Inge K.
VIP
VIP
If memory Razz .......RT did use something similar on the fuel return line just after the FPR, a couple of years ago.....succes all the way back to the tank.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

3Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Fri Feb 09, 2018 5:03 pm

MartinW

MartinW
Life time member
Life time member
The vacuum line on my 75 from the No 3 throttle body vacuum port to the FPR has a spring over it.
Regards Martin.

    

4Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Fri Feb 09, 2018 5:12 pm

Inge K.

Inge K.
VIP
VIP
MartinW wrote:The vacuum line to the FPR has a spring over it.
Regards Martin.

That is standard from the factory.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

5Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Fri Feb 09, 2018 5:25 pm

Inge K.

Inge K.
VIP
VIP
RT didn't use something similar 5 years ago, it was exactly the same.....

Collapsing Fuel Return Line Sany1310


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

6Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Fri Feb 09, 2018 5:54 pm

MartinW

MartinW
Life time member
Life time member
I waiting for someone in the US to post the price of the Unicoil in the US. Collapsing Fuel Return Line 177381
Regards Martin.

    

7Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Sat Feb 10, 2018 11:11 pm

blaKey

avatar
Life time member
Life time member
Martin, have a look here...Post 59.

Got it from Flea Bay here in Oz.

Did the job.


__________________________________________________
Neil
K100RS 1986 RED!

Dress for the ride and the potential slide.
    

8Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Sat Feb 10, 2018 11:27 pm

MartinW

MartinW
Life time member
Life time member
Thanks BlaKey I ordered one from Autobarn on Friday it's supposed to arrive tomorrow. Collapsing Fuel Return Line 112350 The local Pirtek guy  is really helpful, and I really don't buy that much off him.
Regards Martin.

    

9Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Sun Feb 11, 2018 5:19 am

Inge K.

Inge K.
VIP
VIP
Inge K. wrote:If memory Razz .......RT did use something similar

Wrong again Collapsing Fuel Return Line 610153 ......Sorry Blakey......at least it was on a RT.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

10Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Wed Feb 28, 2018 6:00 pm

glennpm

glennpm
Silver member
Silver member
Hi Martin,

The spring would work for sure. Are you sure you had it plumbed with fuel injection hose and not just fuel hose. Fuel injection hose is thicker, made for higher pressure and shouldn't have kinked.

For info: https://grassrootsmotorsports.com/forum/grm/fuel-line-vs-fuel-injection-line/39652/page1/

Glenn

    

11Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Thu Mar 01, 2018 3:01 am

MartinW

MartinW
Life time member
Life time member
Definitely the right type of hose. It just requires a sharp bend and the collapsing only occurred on really hot days 39C in traffic.  So with the spring it's not a problem.
Regards Martin.


__________________________________________________
1992 K75s
    

12Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Thu Mar 01, 2018 8:24 am

glennpm

glennpm
Silver member
Silver member
Good fix with the spring and I can see how the heat would cause it.

Best regards,
Glenn

    

13Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Thu Mar 01, 2018 1:15 pm

Two Wheels Better

Two Wheels Better
Moderator
Moderator
MartinW wrote:I waiting for someone in the US to post the price of the Unicoil in the US. Collapsing Fuel Return Line 177381
Regards Martin.
Amazonia the Destroyers


__________________________________________________
1977 R75/7-100, '93 K11/K12 Big Block, '95 R100 Mystic, '96 K1100RS, '98 K1200RS, '06 K1200R & '09 K1300GT. Projects: 1993 & '96 K1100RS, & 1st '98 K1200RS.
The Mystic, Big Block, 2nd K1200RS, K12R & K13 are running & ridable.
    

14Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Thu Mar 01, 2018 1:32 pm

MartinW

MartinW
Life time member
Life time member
Typical, you can buy an Australian designed device cheaper in the US than you can in OZ.  Collapsing Fuel Return Line 44271 
Regards Martin.


__________________________________________________
1992 K75s
    

15Back to top Go down   Collapsing Fuel Return Line Empty Re: Collapsing Fuel Return Line Thu Mar 01, 2018 1:39 pm

Two Wheels Better

Two Wheels Better
Moderator
Moderator
MartinW wrote:Typical, you can buy an Australian designed device cheaper in the US than you can in OZ.  Collapsing Fuel Return Line 44271 
Regards Martin.
Potential reasons: the tyranny of distance, the 78 cent dollar, economics of scale, and some bastards just mark things up higher in OZ. Strewth.


__________________________________________________
1977 R75/7-100, '93 K11/K12 Big Block, '95 R100 Mystic, '96 K1100RS, '98 K1200RS, '06 K1200R & '09 K1300GT. Projects: 1993 & '96 K1100RS, & 1st '98 K1200RS.
The Mystic, Big Block, 2nd K1200RS, K12R & K13 are running & ridable.
    

Sponsored content


    

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