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Refurbing Greenspeed GT3

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LWaB View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote LWaB Quote  Post ReplyReply Direct Link To This Post Posted: 03 August 2024 at 5:03pm
I am utterly clueless with posting images from Flickr here. Please link me to the forum’s instruction page that tells me what I need to do to make things work.



Edited by LWaB - 03 August 2024 at 5:07pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Anthony-C Quote  Post ReplyReply Direct Link To This Post Posted: 03 August 2024 at 7:17pm


Seeing the hinge open it lacks any contact on the side tabs, but ironically a rubber patch right across the lower half might resist torsion a bit (done up hard)

Posting photos: above the message box select Full Editor (jagged arrow icon).

Edited by Anthony-C - 03 August 2024 at 7:20pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote LWaB Quote  Post ReplyReply Direct Link To This Post Posted: 03 August 2024 at 9:41pm
The problem is that the hinge pivot pin is a loose fit longitudinally and laterally. Torsionally, the two hinge plate rotate around the QR clamping point, regardless of how tight the QR is. You can see the gap on one side. I think reducing the lateral movement at the hinge pivot pin would mostly solve the problem.

Edited by LWaB - 03 August 2024 at 9:42pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote LWaB Quote  Post ReplyReply Direct Link To This Post Posted: 05 August 2024 at 12:51pm
The chain guide tubing on this trike is looking very second-hand, particularly at the fold. What is the right material to use as replacement chain tube? 12mm ID PTFE tubing, polypropylene irrigation tubing or something else?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote LWaB Quote  Post ReplyReply Direct Link To This Post Posted: 28 August 2024 at 4:10pm
I have ordered some PTFE tubing from China, 15mm OD and 13mm ID. These dimensions seem to match the chain tubing supplied by Ginkgo. We will see how it works.

A friend has agreed to try remanufacturing the frame hinge with an oversize hinge pivot pin, as recommended by Pacific Cycles, the GT3 frame’s fabricator. Hopefully that will solve this recumbent’s last major issue.

Edited by LWaB - 28 August 2024 at 4:12pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote nashd Quote  Post ReplyReply Direct Link To This Post Posted: 09 October 2024 at 4:27pm
I thought I'd tag a question or two onto the end of this thread, if that's okay...

I'm working on an old Greenspeed trike which has crossover tie-rods, one of which is bent.  Where can I buy these?

I saw the earlier recommendation for McGill Motorsport for the rod ends.  Is there anything else I'd need to overhaul the steering?  (I'm not a great mechanic, and trikes are new to me, and I haven't started stripping it so I'm not sure how it hangs together).  Will the rod ends be held onto the trike with standard bolts, or will it need bushes etc?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote LWaB Quote  Post ReplyReply Direct Link To This Post Posted: 09 October 2024 at 8:56pm
MR Recumbents on Oz got more of the old Greenspeed spare parts than TriSled but they couldn’t help with our wobbly hinge either.

This GT3, and all the others I’ve seen have crossover steering rods with brake cables routed to the opposite wheel to the brake lever from the factory.

The steering rod ball ends used standard metric bolts through them (no bushes required) and screwed into the hollow threaded steering rod with lock nuts. Our GT3’s steering rods had RH threads all round but WizWheels expected half of them to be LH threaded. No idea if this aspect changed sometime during GT frame production.

Edited by LWaB - 09 October 2024 at 9:39pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote LWaB Quote  Post ReplyReply Direct Link To This Post Posted: 09 October 2024 at 9:38pm
All four GT3 ball joints are 5/16” male RH UNF thread. The bore is 5/16” with an M8 Allen bolt pushed into it.

Your Greenspeed may be different, so check before ordering.

If it is only a minor bend in a track rod and the pair of rods don’t clash, does it really matter that one is a bit bent? Steering forces are very small and the thread on the ball end joints allows you compensate for minor length differences.

Edited by LWaB - 09 October 2024 at 9:44pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote nashd Quote  Post ReplyReply Direct Link To This Post Posted: 10 October 2024 at 9:54am
Thanks very much, LWaB - very helpful.

I contacted MR Recumbents before I bought the trike, and it sounds like some spares aren't available.

The trike was damaged on its way to me.  The chainring was badly bent, and a bar-end mirror had sheared in half (near the ball joint of a B&M mirror).  This in addition to the bent tie rod.   I'm trying to work out what's going on with the steering alignment...

I tied two straps between the handlebars and the crossmember (so that the handlebars were held parallel to the crossmember).  The handlebars also looked parallel to the front edge of the mesh seat when viewed from above.  The right hand wheel (the one without the bent tie rod) has significant toe-in.  I measured very roughly with a tape measure and it might be in the region of 30mm.  The left hand wheel (with the bent tie rod) has maybe 10mm of toe-out.  If the bent rod was straightened then that would increase the toe-out - I'm not sure if it would give 20mm (or whatever measurement would be required to increase the toe-out to match the toe-in of the right hand wheel.  If that were the case then both wheels would be pointing off by a roughly equal amount in the same direction.  If the wheels were then set straight ahead the handlebars would be skewed.  There's not a lot of exposed thread on the tie-rod ends - I could probably extend them, but not shorten them by much.

I'm not sure what's happened to it (I was assured the tracking was perfect before the damage occurred).  I also haven't worked out how to sort it.  Perhaps I just need to keep the handlebars parallel and make whatever significant tie-rod adjustments are necessary, and maybe buy new tie rods and rod ends.

I've asked Trisled for a shipping price for their under-toe wheel alignment tool.  I think it might be a fairly new item, and I'm not sure if it would help in aligning the handlebars to the wheels, but it should help to make the toe-in adjustments easier.


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Post Options Post Options   Thanks (0) Thanks(0)   Quote LWaB Quote  Post ReplyReply Direct Link To This Post Posted: 11 October 2024 at 3:23am
You are aiming at a minimal amount of toe-in, 1-3mm? difference between front and back wheel rim to opposite wheel rim Too much increases drag and tyre wear. Too little (toe out!) gives unstable steering.

Are any frame parts bent or the mountings on the king pins or handlebar pivot?

Edited by LWaB - 11 October 2024 at 3:24am
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