Never put a load into the middle of an unsupported strut

[Stueeee]

Any "beef it up" solution is always going to be a triumph of engineering over poor design. Although you you would be able to ride it quite soon.

With such a narrow chassis it would be tricky to get the coilover mounting further out on the wishbone without having a silly angle or extending the chassis out sideways by quite a bit for the top mounting.

It looks like there's enough room to get a pushrod linkage in there. it would allow you to mount the coilover dead upright right alongside the chassis.

Here's the pushrod setup I made for one of my cars. The pivot runs on needle roller bearings.

 

[tom2207]

They seem to be still using the exact same design , from the web site if Ive got the right maker . So it really might be worth a look on the owners site.

 

[tom2207]

Any "beef it up" solution is always going to be a triumph of engineering over poor design. Although you you would be able to ride it quite soon.

With such a narrow chassis it would be tricky to get the coilover mounting further out on the wishbone without having a silly angle or extending the chassis out sideways by quite a bit for the top mounting.

It looks like there's enough room to get a pushrod linkage in there. it would allow you to mount the coilover dead upright right alongside the chassis.

Here's the pushrod setup I made for one of my cars. The pivot runs on needle roller bearings.
View attachment 241435

tidy solution.

 

[minimutly]

Any "beef it up" solution is always going to be a triumph of engineering over poor design. Although you you would be able to ride it quite soon.

With such a narrow chassis it would be tricky to get the coilover mounting further out on the wishbone without having a silly angle or extending the chassis out sideways by quite a bit for the top mounting.

It looks like there's enough room to get a pushrod linkage in there. it would allow you to mount the coilover dead upright right alongside the chassis.

Here's the pushrod setup I made for one of my cars. The pivot runs on needle roller bearings.
View attachment 241435

Ooo, I like that. Another option for the winter, one leading trike seller has the shocks horizontal, which is good but you need the right shocks (and top arm) to make it work. Looks like it will be a beef it up solution is best for now (both sides @RWD3M ).
Skidding @tom2207 ?

 

[minimutly]

They seem to be still using the exact same design , from the web site if Ive got the right maker . So it really might be worth a look on the owners site.

No, they've moved on to 11/4 tube, load spread across two members, which seems to survive even heavier trikes. I still don't like it though, it offends my engineering eye

 

[Matchless]

I would suggest that the weld has created a stress raiser there, it should have had a spreader plate fitted to the tube and particular care made of the welding to make sure there is no undercut or notching of the welds, you may have the same problem with the anti roll bar bracket, that welding is pretty poor for a pro job.

Looks very good for a trike! I looked at one parked at Bert's tea hut a few years ago, stick welded, badly..........made out of water pipe,

 

[Seadog]

Did you hear that Bert has died?

 

[minimutly]

Looks very good for a trike! I looked at one parked at Bert's tea hut a few years ago, stick welded, badly..........made out of water pipe,

The first one I bought was a death trap - pidgeon poo and even more on top everywhere, I had to cut the whole lot off!

 

[Matchless]

Did you hear that Bert has died?

Just today, funeral on the 24th at High Beech church, 10am, will go on my 41 G3L as Bert rode one in Egypt on National service, he had to collect the post every day, made 89, smoked a pipe and had two women on the go at the same time from what I remember, and probably not adverse to a drink!

 

[minimutly]

This is the updated part.

 

[hermetic]

Crap engineering, simple as! tube is too small and too thin, wishbone load is unbalanced, and a twisting motion is imparted to the lower wishbone at every bump. Just imagine striking a sharp edged pothole with this setup and you have a scenario for instant catastrophic failure. New wishbone with larger diameter, thicker wall tube, plate the bottom and put a shocker on either side of the driveshaft like Jaguar did on the E-type.

 

[angellonewolf]

surely if that make a trike it has to pass a vosa test do they not notice this ?

 

[brightspark]

dunno why they didn't centralise the fixings for the units so would have even pressure over the wishbone I used to make my onwn on the stockcar and none failed or bent. just used to rip the rose joints out or bend them

 

[minimutly]

dunno why they didn't centralise the fixings for the units so would have even pressure over the wishbone I used to make my onwn on the stockcar and none failed or bent. just used to rip the rose joints out or bend them

Good reason for that, the driveshaft is in the way.
Well the lower arm has met my prpoane torch - couldn't see a way atound it - the whole thing was plastic coated - I hate plastic/poweder coat...
I've cut the diagonal out and made up a new tube in 33mm od, wall thickness substantially thicker. Still not decided if I'll move the shock out.

 

[Morrisman]

Good reason for that, the driveshaft is in the way.
Well the lower arm has met my prpoane torch - couldn't see a way atound it - the whole thing was plastic coated - I hate plastic/poweder coat...
I've cut the diagonal out and made up a new tube in 33mm od, wall thickness substantially thicker. Still not decided if I'll move the shock out.

If you move the shocker location out further towards the hub you’ll need a softer spring. If you’re happy with the ride as it is I’d leave the geometry the same, or you could be opening a can of worms.

 

[minimutly]

Thanks, I knew that.
Edit to add, This is the dilemma, but, because it's so far in now, the spring, shock/bushes, are having a hard time, not to mention the inner arm bushes and frame.
Going to get some 5mm flat steel this morning, maybe make some +50mm mountings, and a plate to link the arms and put a pair of shock tabs in. The arm is made, just one weld to make, I didn't want it pulling.

 

[minimutly]

Decided to repair with options for now, moving the shock out would have been relatively easy, at the top by making bigger lugs, and expanding them up to the rack bar above, thus spreading the load. However, it would mean burning the coating off, and cutting and rewelding the upper arm, and recoating the whole lot, as well as changing the springs.
Job for the winter. The modified bottom arm will be able to accept a 50mm shift out at a later date.
Pics when its made.

 

[angellonewolf]

would like to see pics when your done

 

[addjunkie]

surely if that make a trike it has to pass a vosa test do they not notice this ?

No it doesnt as its a bolt on kit, even if it did go through the MSVA test, they dont check design detail, its more like just a supper mot. They may ask for steel receipts etc too, but no formal sstructural design assesment, calculations or even weld tests or competencies for that matter.

If it was built is 2008 its not done too bad, being such a poor design. Trike building is a dark art, the MSVA introduction has driven the majority of builders towards bolt on options, but it fortunatley has removed much of the old bedframe, scaffy tube, incorrectly registered desth traps.

 

[minimutly]

Correct @addjunkie