Girder central spring

Thomas · May 24, 2020, 11:59:01 AM

Thanks a lot, Vic! So, there's no spring available? I already have a new primary chain and then will see if the vibration is gone with the new sprocket. If not I will turn the spring upside down.
All the best, Thomas

VicYouel · May 24, 2020, 11:11:33 AM

Thanks for the measurements of your spring and it would still be nice to know what is like when reveresed. Even with the details from my 1938 Terry's catalogue and in discussions with Graham at Alberta I am not sure where we from here to help you with your 1937 AMC produced machine, Sorry
Vic

Thomas · May 16, 2020, 06:06:28 PM

Hm, I didn't check that.

singleminded · May 16, 2020, 08:22:28 AM

Does it look better depending on what end it is mounted?

Thomas · May 16, 2020, 07:05:51 AM

Yes, I did, the spring seems to be distorted only when complete installed.

singleminded · May 14, 2020, 10:35:11 PM

Hi Thomas..if your fork spring is supposed to be symetrical end to end have you tried screwing it on to the bottom girder fitting ,without fitting the top, from each end of the spring. This may give you a better indication of whether one end of the spring is distorted. John

Thomas · May 14, 2020, 03:31:35 PM

Watch out, lying doesn't help! The company collects metadata via the IP address even if you surf outside Facebook. After a while they have your complete surfing track and know you more than you expect.

kbryt · May 14, 2020, 02:18:47 PM

Concern with FB privacy? do what I do, use a one off email address, and when it come to personal information, tell lies..........

Thomas · May 14, 2020, 10:08:02 AM

Great! I just sent an email. I once got an invitation to a WhatsUp group and to Facebook. Unfortunately I have no smart phone and do not like Facebook with all their privacy issues.

VicYouel · May 14, 2020, 09:26:32 AM

Thomas
I wonder whether you can let me have your email address please....... my contact details are given in Beaming. You may also find it useful to correspond with the model interest group and possibly make enquiries on the Martson-Sunbeam Facebook site.
Best regards
Vic Youel (club new spares officer)

Thomas · May 14, 2020, 08:34:45 AM

Ah, they told me that they have asked somebody in Scotland but didn't tell who it was.

I already asked Graham for a new spring but didn't get an answer yet. I assume that 10 inches are the correct length but have no idea if that will help and focus first on the sprocket then on the flywheel and its bearings according to the respective workload. After dismantling the sprocket I couldn't feel any wear in the bearings when lifting the crank.

Cheers, Thomas

VicYouel · May 14, 2020, 08:15:59 AM

Alberta Springs have asked me for help on this! The spring we have in stock was based on Alberta drwaings and has been used by another member on earlier 1930's models.

Thomas · May 08, 2020, 01:26:26 PM

Yes, this is difficult to judge. The last winding on both sides is somewhat off center which might introduce the visual distortion when installed. When looking through from one end to the other, everything's centered. I have no feeling if that's ok or not. I contacted Alberta Springs again and wait for a comment. Maybe better buying a new one instead of tricking around.

kbryt · May 08, 2020, 01:05:49 PM

sorry Thomas I have trouble editing photos here.

The spring is not distorted off the bike as it is no longer under load.
you really need an original to compare now.

Thomas · May 08, 2020, 12:55:53 PM

I got the spring out. But now I'm really lost. It's not distorted at all and the connections are fine...

Thomas · May 08, 2020, 12:32:02 PM

Great! But what are the "top links and rearmost spindle"? Can you indicate in my pictures?

kbryt · May 08, 2020, 12:08:56 PM

as best as I can from memory

remove handlebars and front brake cable
remove top links and rearmost spindle
undo the large stem nut and the bolt in the top of the spring
remove top yoke then the rest will fall out

Thomas · May 08, 2020, 12:00:45 PM

I started dismantling the fork which is straight forward until now. Lamp and speedo are off but how do I proceed? I have no idea how to get the girder off the steering axle.

Thomas · May 08, 2020, 07:20:24 AM

Attached is better photo of the spring from my last thread. It's really distorted! That might be the reason for its strange enveloping behavior. I presume I have to install a new one. Is there any supportive text available for the dismantling of the fork?

I have seen that the spring in the club shop is 10 inch long (25,4cm) whereas my spring is significantly shorter (about 21.5cm). For BSA the spring is also 10 inch long and I now wonder about the correct length.