Shakin' Strumpshaw Steam Rally

This years Strumpshaw Steam Rally provided the perfect opportunity for a decent ride, a lovely day out and the chance to shake out some more SQ4 problems.

Strumpshaw is a village in my home county of Norfolk located on the northern bank of the River Yare around 6 miles south-east of Norwich within the Broads National Park. The village lies a little distance from the river, on the slopes of Strumpshaw Hill, the highest area of land in the Norfolk Broads.

Strumpshaw Hall lies closer to the river, next to the Yarmouth & Norwich railway line from Norwich Thorpe to Yarmouth Vauxhall, first opened in 1844. It is the home of the Strumpshaw Hall Steam Museum, with a collection of traction engines, steam rollers, 100-ton working Beam Engines, a Narrow Gauge Railway, a 1930s Fairground, Mechanical Organs and much Memorabilia collected over many years by the Key family.

The Strumsphaw Steam Engine Rally is held each Spring Bank Holiday Weekend in the beautiful parkland grounds of Strumpshaw Hall. The rally hosts over 50 traction engines in steam and some 350 other exhibits including vintage tractors and heavy horses, stationery engines, fair organs, working demonstrations of steam and tractors, classic cars, trucks, fire engines and motorcycles.

It's the perfect spot for a ride out to meet the grandchildren, especially if the weather promises to be sunny.

The ride down quickly revealed that the steering problem had been fixed by proper adjustment of the wheel alignment, but that the chainguard was still a problem.

This KTM was the only bike to join me in the car park... It looks like all the other bikers registered their bikes as exhibits and got in for free:

The best part of the shakedown was the results from the carburetter temperature testing. After a 69 mile round trip with no misfire, and a 22 mile trip back at 55-60 mph we have these results, taken with the engine running in the yard and measured immediately upon arrival:

• 208°C on the fins near No.2 spark plug
• 131°C on the inlet manifold flange - near the offside carburetter stud
• 80°C on the carburetter flange, 1/2" from the 131°C measuring point but on the other side of the phenolic spacer. That's a 51°C differential across the spacer.
• 47°C on the float bowl.

Ambient was around 20°C for most of the trip. I measured the other cylinder head temperatures as well and added them to my chart with some previous tests:

Looking at these results, there is an issue around the focus of the thermometer. Normally I point the targeting laser on the plug body from about 15" away, which probably means we are measuring a 2" circle around the plug body; for Test 5 I aimed the laser at a fin and probably ended up measuring the plug insulator, explaining why the temperature is much higher. Consistency is the name of the game as any test engineer will tell you.

It appears that I haven't fixed the oil tank cap leak - maybe the gasket is not thick enough. I think it is better as the oil wasn't in the toolbox this time, but we have not solved that one yet!

And as the day drew to a close, I was left wondering how many of the Strumpshaw Ten Commandments might apply to riders of Square Fours...

Trip to the City

An eye test gave me an excuse for a trip to the city yesterday: not a particularly nice day, but the SQ4 has not been out for a bit so it was time to stretch her legs.

I chose an A-road route outward, with 60 mph stretches for several miles and she is flying along; a mixed A & B-road route back gave me more of the same with some twisties and peaceful roads at the end:

At the start of the trip, the early morning starting ritual revealed the carburetter flooding: switching off, starting the engine, and switching on again, the flood did not repeat itself - I think the float sticks occasionally.

On the road, my 28/24 psi front/rear tyre pressure combination may be questionable. The front end feels light and not terribly planted - I may need to reduce the pressure on the front. The bike wants to drift to the side of the road so I think I will look at the wheel alignment.

In town traffic, in the morning, you can feel that she's not happy. She gets hot, and the carburation appears rough - not too bad to be called a misfire but not relaxing either. Arriving home, I noticed the same arriving in our small seaside town, and you can see oil on the HT leads so perhaps this is not carburation at all. The clutch also starts to drag a little, so maybe some adjustment there.

Stopping to pick up some Argon on the way back (The TIG welder is hungry again) I noticed a slight clonk when moving the handlebars - this may not come from the front end, but needs investigating.

I also noticed a little oil leak, two in fact - both from the primary drive, one at the clutch and one at the front. The chain is also not getting any lubricant.

I had the LED headlamp on all the way back - it's nice to see the bike balances charge in town with this fitted. Not so nice was the flickering rear lamp apparent with the bike idling, when I took these pictures. I also noticed that I had lost one of the 4 BA screws that retain the ammeter/switch panel to the headlamp. More fool me, for not fitting shakeproof washers!

So, a few little jobs (including the perpetual speedo fault) but generally a grand day out. I must have been going some, because my shoulders ache this morning!

Steering Lock

As part of the fork rebuild, I bought a steering lock for the Huntmaster from Draganfly. It fits in this forged lug on the bottom yoke, and it was obviously not originally fitted - the lug was full of maroon paint. It pushes in from underneath and is retained by a grub screw:

Here's the frame lug that the steering lock pin will fit into one day:

This next shot, which comes from someone on the AOMCC forum, shows the frame lug for the steering lock pin with the yokes in place. I guess that thin sheet over the top is to prevent the potential thief removing the lock by punching it out from above:

A little trip to Cromer

An evening ride to Cromer revealed a front brake that was much better, but which now had too much lever movement. Nipping up the adjuster two clicks improved the lever movement and there didn't seem to be any brake binding, which was excellent. There was still a juddering from the front, particularly on braking. Getting it home, I found that wheeling the bike backwards revealed that particular groan that only binding brakes make, so I've backed the adjuster off one click.

Back in the workshop, a quick check revealed loosened head bearings - wheeling the bike forwards and putting the brake on reveals a 'jolt' from the headstock which you can hear. To check them more physically, put the bike on the main stand and put your thumb here in the dim & dark recesses of the top yoke, across the gap between the dust cover and the headstock:

The Engineer's Thumb

With your other hand, grasp the front wheel and rock the bike backwards. This has the effect of pushing the steering column up through the headstock against the weight of the bike, and your thumb will be able to feel any movement. Don't vigorously rock it backwards & forwards - you don't want it rolling off the stand.

Mr. Waller suggests lifting the weight off the front wheel to perform this job, bit since I have no bike lift or any desire to damage my back I use the method described above.

So, having found some movement we need to sort out the problem. First slacken off the lock nut under the top yoke with your head race spanner. Clay at Acme Stainless has these, but you can also pick original ones up on eBay. Be very careful not to damage the paint on the tank - make sure the spanner fits well (so that the spanner doesn't slip) and that the tank is protected (for when the spanner slips):

Now, grasping the wheel again, roll the bike backwards against the main stand whilst attempting to tighten the lower of the two nuts. You will find that the nut is now loose and can be tightened down - you will want to perform this feat of coordination two or three times.

When you are happy that the bearings are snug, and you can feel no more movement, tighten down the top nut. Move the handlebars and satisfy yourself that they are not binding anywhere. 

If you use your steering damper, reset it and you are good to go.

Building up

So, a few shots of half an hour's work, putting in the yokes:

Bottom bearing greased...

Steering damper parts all assembled. All from Drags bar the star washer and centre stem which are original

Top bearing greased

Bottom yoke in & bearings adjusted.