Rear

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Rear Suspension

Two types of rear shock absorbers were fitted to the T300 range of motorcycles. Neither types are re-buildable, some companies will say they are, however don’t believe them. Suitable replacements are:

Manufacturers - Approx. Price
Hagon YSS Nitron Maxton
300 300 500 500

The Speed Triple Challenge bikes used Proflex rear shock absorbers, however these are no longer available new. These also increased the rear ride height which sharpens up the steering.

Replacing

Replacing the rear shock absorbers is a common operation, and covered fully by the Triumph Workshop or Haynes manuals. Typically this is needed when the:

  • Shock absorber fails [unlikely]
  • Failure to provide adequate suspension due to age, high mileage
  • Updated for a astetics (corrosion/paint/etc..), road or race situations

Should luck prevail you will be able to follow the manual and remove the shock in-place by lowering the swingarm and removing/replacing the shock from the top of the bike. This however is unlikely due to age and prior maintenance.

Corrosion of the suspension linkage spindle dust covers causes the spindle to either not move at all or only rotate in place. The spindle needs to be removed fully to withdraw the monoshock; and apply some maintennace.

Note: Two type of suspension linkage exists, one with pinch bolts and a later type with a grub screw arrangement. If the pinch bolts are overtightened it can cause the linkage to crack and break and will need to be replaced. Ensure these retainers (pinch bolts or grub screws) are removed before you attempt any removal of the spindle.

Suspension Linkage Types
LinkagePinchBoltType.jpg

Early Type. Failure due to over tightening.

LinkageGrubScrewType.jpg

Later Type. Modified linkage with bolt and nut.

The following approaches will help remove the monoshock from the bottom linkage:

  1. Penetration fluid may loosen the spndle and with rotation it can be removed
  2. Screwing the large end caps back on and using a soft/wooden mallet to shock the spindle free
  3. Apply some heat and step 2 again. Note to be careful with the heat due to the roller bearings and rubber inside the dust covers
  4. With the end caps removed, put a threaded bar into the tube and with a socket / washers & nuts, slowly wind the spindle out
Removal using threaded bar option.

Often a culmination of all 4 will be needed. Follow the manual to re-fit, apply plenty of lubrication.

Swing-arm

These when manufactured by Triumph were anodised (black/silver) and in the course of 20+ years can get a little scruffy. Triumph have no swing-arms in stock, so refurbishment is the only recourse. Paint or powder coating are options, but of course care must be taken in masking off holes and bearings. Bearings/holes can be blanked of with some big washers to prevent grit getting in when blasting prior to powder coating; your painter should do this as standard. It may be necessary to replace the needle roller bearings.

If you replace the needle roller bearings, buy from a Triumph dealer, use OEM parts or ensure the quality is suitable as 'caged' and 'non-caged' have an impact of the load they can sustain. Many online sellers provide the cheaper quality ones!

For Daytona Super 3 (III) owners there is an additional problem. The Super 3 has a carbon fibre rear hugger and the carbon fibre can react with the aluminium in the swing arm causing corrosion. This is a well known problem in the aeronautical industry where carbon outer panels are fixed to the aluminium frame ( I have an aero engineer friend who says this has become a serious problem). The slight “fretting” and flexing of the swing arm and hugger causes minute scratches in the micro thin anodising allowing the aluminium to come into contact with the carbon fibre and then a reaction is creating causing “rot”.

Below are 2 photos of a swing arm of a Super 3 suffering from this. The solution is not simple, in the aeronautical industry a special agent for killing the rot is first used and then a special filler. The downside is that this treatment is very expensive, when I looked the smallest quantity of both compounds was in excess of £200. The carbon fibre hugger must then be isolated from the swing-arm with the use of thin rubber washers.

Suspension Linkage Types
Swing arm corrosion 1.JPG

Corrosion across the stiffening plate.

Swing arm corrosion 2.JPG

Corrosion RHS.

The only other issue with the swing-arm is caused by not following the torque settings for the adjuster/clamp pinch bolt. This should be set at 36Nm and no more (see Triumph workshop manual). If this bolt is overtightened then the swing arm will crack and this is not repairable under any circumstance.

SwingArmPinchBlt Cracked.jpeg

Over-tightening of the pinch bolt causes fractures.

See Also

Parts suppliers