Valve shim removal tool procured. New measurements taken. Additional shims ordered.

Current odometer reading: 44844 miles (no additional miles travelled since last work)
Valve shim tool arrived, and allowed removal of valve shims and size readings.

Valve shim tool.png

More accurate valve clearance measurements (current) were taken, along with the shim sizes of shims to be replaced. Information as follows (shim readings are in brackets):

Inlet 1:            0.1     (280)

Exhaust 1:     0.17   (260)

Inlet 2:            0.09   (280)

Exhaust 2:     0.23

Inlet 3:            0.16

Exhaust 3:     0.2

Inlet 4:            0.11

Exhaust 4:     0.17   (265)

The following replacement shims are to be procured:

275 (for inlet 1)

255 (for exhaust 1)

275 (for inlet 2)

For exhaust 4, the 260-sized shim from exhaust 1 shall be substituted.

Front brake rebuilt with new pads and seals and fresh brake fluid. Diversion decals removed. New mirrors fitted.

Current odometer reading: 44844 miles.

Front brake rebuilt with new pads and seals. The old pads have been retained and put into storage as spares, as they are in good condition with lots of wear remaining. All front brake fluid bled and replaced.

Larger mirrors fitted (road-riding oriented, with better visibility).
new mirrors fitted.png

All standard Yamaha Diversion decals removed (personal preference).

decals removed.png

Carburettor cleaning and valve clearances check

It was necessary to check valve clearances, and this can only be done by removing the carburettors first. As the carburettors were off the bike, the opportunity was taken to carry out some basic tasks on all 4 of them, although not a complete disassembly:

  1. Clean float bowls.
  2. Clean all jets.
  3. Inspect diaphragms.
  4. Polish main jet needles.
  5. Reassemble carbs.
  6. Reset pilot mixture screws 2 turns out, as exactly as possible.
  7. Bench sync as exactly as possible.

The product used was STP Carburettor Cleaner Spray. The jets were removed and left to soak in a jar full of this cleaning solution, and were then blasted through with the spray nozzle. The jet holders were also blasted with carb cleaner. Float bowls were also cleaned and rust particles removed from them. The jet needles were polished using carb cleaner and aluminium foil.


The rocker cover was removed to check the valve clearances. At the same time, the opportunity was taken to clean under the rocker cover bolt seals. The valve measurements were taken and are as follows:

Inlet 1:           0.12

Exhaust 1:    0.15

Inlet 2:           0.1

Exhaust 2:    0.23

Inlet 3:           0.11

Exhaust 3:    x

Inlet 4:           0.1

Exhaust 4:    0.25

The measurements taken are all within spec with the exception of the exhaust valve on cylinder 1. However, the inlet valves are all on the borderline of going out of spec. It was not possible to see the sizes of any valve shims, as a valve shim tool to depress the valve baskets and remove the shims is still being procured.

New battery and air filter fitted

Odometer reading: 44670

New battery fitted as a precaution following the smell of sulphur under the seat when riding.

New filter (HiFlo Filtro brand) was fitted, as the cleaning undertaken shortly after bike was acquired consisted solely of blasting with compressed air (as per Haynes guidelines), and was insufficient to clean out the smaller particulate matter/air pollution (as the photo shows).

Rear brake revisited (complete rebuild)

The brake was sticking on the left side, as a seal had perished. It was decided to completely rebuild the brake.

Caliper split and thoroughly cleaned with solvent. Pistons polished. All seals replaced (Tour Max seals made in Japan and sourced from Wemoto) Brake rebuilt and all brake fluid bled and replaced. Sticking problem solved. The brake grabs strongly and releases completely.


Cosmetic work – tank

Clutch plates and springs tested and working 100%. No leaks nor any hard changes up or down. Current odometer reading: 44644 miles.

Hardened remains (melted rubber and adhesive) of old tank pad and deep scratches in the tank were a minor annoyance. It was decided to mask these flaws with black gloss paint, after preparing the affected area. Future plans for the bike include a JPS colour scheme. Hence, this remedial act is not expected to be final.