For advice on setting up suspension I'd recommend the Revs Racing site which has a Set Up section dealing with what you should do with all the screw, spanner and knob adjustments available on modern bike suspension. The Revs Racing site is at http://www.revsracing.co.uk .
The forks on the Sprint Sport are the 3 way adjustable Kayaba units that were fitted to the modular Daytonas and Speed Triples. They are of reasonable quality and do an acceptable job of absorbing the bumps and steering the bike. The overall balance of the front end of the bike - forks, brakes and steering geometry - is very good with the forks able to cope with the weight of the bike and the wonderful 4 pot brakes (as fitted to the newer, alloy framed, Triumphs) without any undue drama.
I changed the fork oil at 2 years as per the service schedule, removing the fork legs from the yokes / triple clamps to do so as there are no drain plugs. I was very careful to pump out all the old oil (silvery and only slightly emulsified) and then replace it with the prescribed level of fresh oil. Once all was back together I was not happy. There was a definite tilt in the forks under braking. I wondered if I was imagining it (I can be somewhat self critical) but finally came to the conclusion all was not well. I obtained a syringe, some clear small hose and a piece of steel rod and assembled the fork oil level adjuster the accessory outfits charge 15-20 pounds for. I removed the front wheel and mudguard (they collide with the fairing otherwise), removed the tops of the forks and the springs with the forks still in the yokes. I then fully compressed the forks together (with the front wheel spindle in place) rather than separately to measure the oil level - and sure enough the 'softer' leg was quite a bit lower. I can only assume this happened because of an air lock in that fork when I did the job before - demonstrating the problem of only having an oil level figure rather than a capacity figure for each fork leg. They are now adjusted to be the same and the bike handles fine again.
Other than the routine maintenance the forks haven't received any special attention, other than adjustment to the settings. I have the settings something like what the owners manual suggests. After owning the bike about a year I increased the preload and damping on the forks and rode like that for a year or so. Over that year I lost about 20 lbs (10Kgs) and wondered why the bikes suspension was so firm!!! It's back to approximately standard now. I can't actually tell you what the settings are at now as I can't remember - all I know is that it feels about right.
The Showa Rear Shock on the modular Triumphs gets a tough life. When new it is a 'budget' piece of kit that is adequate but is never going to be a sparkling performer. The weight of the bike makes it work hard and the larger rider that the size of the bike attracts, quite often with a pillion as well, just goes to make its life tougher still. At least on the Sprint Sport there is the mudflap arrangement to ensure it doesn't get covered in road filth which is more than some of the earlier bikes had. It would have looked better if the hugger from the Daytona had been fitted though.
By the way, I do realise that what I describe as the 'shock' is actually a complete suspension unit with spring and damper (shock absorber) built into a single unit. Shock is just easier to say and most people will understand what I mean. I believe the only modern bike with separate springing and damping is the Suzuki TL1000S and possibly the R.
After about 4 years I decided I wanted a bit more handling performance out of the bike. The rear shock wasn't completely shot but it certainly wasn't improving with age and increasingly I was finding that fiddling with the limited (4 position) damping settings on the standard unit was having little effect. Something needed to be done! But what?
I'd found Revs Racing on the web when looking for someone to rechrome and grind the fork stanchion tubes on my old Yamaha DT175MX. John Gaskell (who is Revs Racing) arranged this, the (cosmetic) rechroming of the cap bolts, supplied the necessary new seals and provided good advice along the way as well. I went to see him about the Triumph and asked about an Ohlins rear shock. He advised against the Ohlins on grounds of price and value for money and suggested the Technoflex unit instead. He supplies and services both types (together with several other makes) so knows what he is talking about.
Basically the Technoflex is:
So how has it turned out? Initially I was pleased because the bike seemed much more comfortable. I set the preload up and then loaded the bike and rode to the Isle of Man for the TT. This was fine but after I unloaded the bike I realised the preload was quite a bit too high for just me so I reduced it. This was better and I had a great time riding round the Island but something still wasn't quite right. I then started to tinker with the damping by increasing it a little. This just made things worse. It turned out I needed less damping as the spring wasn't able to recover fully after a bump before the next bump arrived. Reducing the damping made it about right.
All this tinkering took about a month all in all. At the end of it I was wondering if the new shock really was an improvement after all. Had I wasted my money on a 'designer accessory'? Then I realised that I was riding corners, bumpy corners at that, more confidently and about 15mph faster than before. The reason I was feeling 'unimpressed' was that the shock was doing it's job properly and not drawing any attention to itself. I believe this is the most impressive aspect of the new suspension.
Would I recommend this upgrade? You bet!
As a final point, I went to Revs and ordered mine face to face but I believe they can be supplied mail order. John has informed me that web ordering is on the way. To get one contact Revs for more details.
Fitting the new shock is a relatively involved job. Not actually difficult in any specific way but there is quite a bit of dismantling and cleaning to be done.
The first thing to remember is that the Sprint Sport as standard has no centre stand. As I have fitted one I was able to just put the bike on the stand and this lifts the bike by the frame so removing all the weight from the rear suspension. A swingarm supporting paddock stand will NOT do as the suspension is still in compression when the bike is jacked up. As to how to do the job without a centre stand then there are paddock stands available that lift the bike by the swingarm pivot - but this would still have given me problems, as the description below indicates. Other than this options include suspending the back of the bike from a suitable overhead support or jacking the bike up under the engine although this would involve removal of the exhaust downpipes - ugh! Additionally if you choose to jack the bike up under the engine I would suggest using a large piece of wood to spread the load - you don't want to crack the sump!
The way it is supposed to then happen is:
"Reassembly is the reverse of dismantling" as the Haynes manual is so fond of saying!
The reality was stages 1 - 3 were fine. Then I hit a snag of fairly major proportions with removal of the lower linkage spindle. It had seized. Solid. Not even a hint of movement! The normal application of penetrating oil to the affected areas both from the outside and down the lock screw holes (with the grub screws removed) had no effect! The next normal solution of application of heat was not a good idea due to the presence of all the bearings and seals which would have been destroyed, the confined space to work in and, worst of all, the presence of high pressure nitrogen (I strongly suspect - if you know better let me know) in the shock body!
Hitting seven bells out of it with a mallet was also not favoured as this would definitely destroy the bearings at the front of the LinkageArm and might destroy the arm itself and damage the frame where this mounts!
Plan A involved obtaining a nice big bolt with the same thread as the linkage spindle (18 diameter with a fine pitch, a nut to suit and some washers larger than the linkage spindle o/d. This was used as a drawbar arrangement to pull the spindle out of the linkage. See the diagram for details. The redesigned spindle on the late bikes (see below) allows this. It would not be an option on earlier bikes. This, unfortunately, didn't work: the shaft was just too well seized. Doh!
Plan B involved reverting to the 'hitting seven bells out of it' approach! As discussed above this wasn't a realistic option with the linkage still attached to the bike so I went to remove the linkage, spindle, shock and connecting rods in one piece. This involves some movement of the exhaust downpipes and collector box etc under the engine but with care can be achieved without having to remove the pipes.
Once the front spindle of the linkage arm had been removed removal of it and the shock proved impossible without lifting the bike by about a foot as the shock couldn't be manoeuvred out between the frame and the swingarm. That meant the swingarm had to be removed! By the time I'd reached this stage I was in 'what the hell' mode. Removal of the swingarm was relatively straightforward, just remove the rear wheel etc. disconnect anything attaching between swingarm & frame and then, after removing the caps on the frame, remove the swingarm spindle. The only points to note when doing this are to make sure the dust seals on the main swingarm bearings don't get lost or mixed up and don't lose or mix up the collars that fit in the bolt holes attaching the connecting rods to the swingarm. Once removed the shock and linkage arm can be easily removed. Stripping the bike down like this does leave it looking very odd!
This finally put me in a position to get to work on the linkage spindle. You may remember this holds the rear shock to the linkage arm and needs to be removed to be able to change the shock! To avoid damaging the spindle, its internal threads or the linkage arm when using a mallet on it I used the bolt from Plan A as the drift. This was screwed securely into the spindle to ensure the threads would not be damaged.
Then a length of pipe of an internal diameter large enough to allow the spindle to slide inside was butted up against the other end of the linkage arm/spindle. I used a piece of scaffold tube I had in the garage. You may want to use a washer between the pipe and the linkage arm to avoid damaging the surface of the linkage arm with the edge of the pipe. The other end of the pipe was wedged against something solid - the side of the garage in my case! Then the bolt was hit smartly with a heavy mallet. See the picture if I haven't explained this awfully well! Be warned that if it requires application of this much brute force then there may be damage to the outer surface of the spindle and the bores in the linkage arm. There was evidence of both corrosion and some scraping from the forcible disassembly in this case but I didn't rate it as terminal and with a careful clean the parts proved reusable!
Once apart all the parts were cleaned and then the linkage was reassembled with the Technoflex shock in place. The swingarm was given a thorough clean but the bearings were not removed: I was very careful to seal them up with studding, nuts and large repair washers before cleaning commenced. The same technique was used with the linkage arm and connecting rods when they were cleaned.
The picture shows the linkage components once disassembled before cleaning. You can see the corrosion on the linkage spindle in the top right of the picture where the elements worked their way between the alloy forging of the arm and the steel of the spindle. Note the tie-wraps used to keep the bearings and dust caps in place after the bolts were removed but before the linkage could be extracted from the bike.
When the swingarm is re-installed ensure the spacer that goes between the two inner plates in the frame is in place and when locating the swingarm be careful the dust caps on the main swingarm bearings are not displaced.
When the linkage spindle was finally reassembled a small amount of copper grease (anti seize compound) was smeared in the bores of the linkage arm. Whether this will have much effect in helping to prevent corrosion in future only time will tell. The original Showa shock has a phosphor bronze bush in its bottom mounting. The Technoflex unit has two white metal bushes that are quite a close fit to the shaft so I found it a good idea to press the shaft into the bottom mounting prior to final assembly. This allowed the removal of the small amount of white metal that was scraped out as it was fitted so it didn't get left in the final assembly.
Once the suspension was completely put back together all the grease nipples were given a good pumping of new grease to ensure all the bearings were well packed. I realise that it is possible to over pack but I'd prefer a bit of grease squeezing out and a slight over straining of the seals to a seized suspension joint.
The Haynes manual has nice helpful pictures of a suspension Linkage Arm that has the outer spindle holes slit and fitted with pinch bolts which are loosened to remove the linkage spindle. The linkage spindle itself is a hollow bolt arrangement with a head with a grease nipple in its end, and a screw in cap at the other end, again with a grease nipple in it!
That's all well and good but the arrangement on mine, and I assume other later Sprint Sports and presumably Trophies too, is different! The linkage spindle is basically a hollow shaft with no 'bolt head' on it. Instead it has two of the screw in caps with the grease nipple in: one at each end. This is held in place not with pinch bolts that clamp the linkage arm to the spindle, but instead has 2 small holes drilled and tapped in the linkage arm where the slits are on the earlier one. Into each of these holes is screwed a 3mm allen headed screw. This must be undone before the shaft can be withdrawn.
I believe this change is partly what gave rise to the problems I had with dismantling the rear suspension. Because salty water and road filth gets in between the alloy linkage arm and the steel shaft and causes corrosion all 4 holes in the linkage arm are gripping the shaft, rendering it immobile. If the pinch bolt arrangement was still in place then the outer holes would be looser when the pinch bolts were undone and would allow penetrating oil in and so only the inner holes would be gripping the shaft. In the event, the inner holes are less of a problem anyway as the grease in the linkage is squeezed in either side of these holes preventing the ingress of salty water and road crud anyway.
I've since been informed (Thanks, Paul) that the older design is just as capable of seizing rock solid as the new one. If Paul lets me know any insights on getting around that problem when fitting his White Power shock then I'll include them here!
To be fair to the new arrangement I'd guess it is probably more rigid, but I reckon that the main reason behind the change is it is easier to drill and tap one small hole each side than to slit and drill the pinch bolt arrangement. Releasing these locking screws and twisting the shaft once a year now forms part of my maintenance schedule along with pumping some grease into the various grease nipples in the suspension.
