My new projekt/bike 55 SQ 4 MK ll

[rschurr]

Hi Simes,

all my other bikes have rigid frames so I can judge what the difference is. I was always dissatisfied with the wobbling of the SQ 4 after a bump.

At first I loosely fixed the friction dampers and braked with the rear brake: the usual jiggling *). Then I hopped over the selected bump (ugly railroad crossing): the usual jiggling.

In three stages, I then gradualy adjusted the friction dampers and made each of the tests as before.

Result for me : Significant improvement in behavior, comes close to the rigid frame with the difference that you have (some ) suspension!

Cheers
Rudy
*) There is also some movement "Feeling" at the fork at the begining of a hard front braking, it is the same for the Ariel as for the BSA
I got used to it

[john.whiting]

For those interested in friction dampers,these are known as "Andree-Hartford " dampers,and may be available commercially from vintage car clubs such as Austin 7,or Morgan .I once fitted some hydraulic type dampers used on the front axle of the WW2 GMC and Studebaker 6X6s on a plunger suspension bike.These are quite a compact lever type unit and are easily clamped to a frame downtube....like all surplus stuff,used to be very cheap.

[rschurr]

Found only theese on "evil bait":

https://www.ebay.co.uk/itm/2x-vintage-c ... =R40&rt=nc

perfect look, but a little bit oversized for this task and not really cheap.

Mine were quite simple but functional and under £ 30 (and a few hours of tinkering).

Rudy

[rschurr]

Yesterday I was with the SQ4 at a local vintage motorcycle meeting . We have driven a circuit with about 50 miles on small uneven, winding roads. The SQ was running fine and the damper system worked very well. According to the motto: do it and forget it.

There were also some interesting english bikes (BSA M20, Scott flying Squirrel, Ariel VG) with us, but also a Moto Guzzi Falcone with it's more sophisticated friction damper system for the rear suspension.

Falcone.JPG (54.66 KiB) Viewed 3803 times

[rschurr]

You have to be lucky!

The ubiquitous valve noise suddenly became louder and the right exhaust had blackish color. When I got home after careful driving I took off the valve cover and seen this:

Valve Clearance Fault.JPG (48.32 KiB) Viewed 3802 times

I found the nut in the cylinder head. Luckily, it didn't fall down to the camshaft.

When I look at this and the defacement of the rocker arms (chamfering or butchering ?)
I have some concerns in the handicrafts of my PO's.

[simon.holyfield]

That chamfering is a common modification - though not very elegant in your bikes case. You are supposed to form a knife edge on the top of the rocker to discourage oil from running down toward the valve guide.

It's shown in later editions of Waller.

[john.whiting]

been done by an imbecile..... ground on the wrong end of the rocker.......,as well as being an outrageous bodge.......Ariel went to the trouble of shot peening the rocker to stop stress fractures.........It reminds me of a Mk1 where some idiot had ground a large lump from the crank so it would run on three cylinders.....needed to be balanced...And he was proud of the effort........One of the many reasons I would never want another S4.

[rschurr]

Have got this week the important vintage motorcycle report and the german TÜV (GB MOT?)
The SQ4 behaved very well and did not lose any oil (at least during the test).
This lovely bike is now ready for a normal road use.

Cheers Rudy

[simon.holyfield]

Congratulations! Is it difficult to pass the TÜV test on a vintage bike? I guess there are special rules for emissions & indicators etc.?

[rschurr]

Hi Simes,

The vintage motorcycle report allows admission to favorable road tax and insurance conditions!

Key points are of the classic review and TÜV report are:

• The vehicle must be safe in traffic and operational conditions, the current main inspection must not detect any significant defects.

• The vehicle should be well preserved and largely correspond to the original condition.
It must not have been made modifications that are not typical of the time or greatly affect the original appearance
The painting should be in a well-maintained condition.

• The exhaust system must be original, or reasonably adequate in terms of volume, function and appearance.

• Vehicles with first registration after 01.07.1969 need also an emissions test.

• Engine and transmission must be original or from a vehicle of the same model

• Chassis and wheel / tire combination must be original.