Friday, September 12, 2014

A rack for going places, after a big trip to Norwich

Tim sent me a rack that was surplus to his requirements. Cool. I'd been on a big trip with my son earlier in the summer. We went to Norfolk for a weekend; a 500 mile round-trip from Somerset. It was wet but lots of fun, including a stop at an american diner. I'm guessing it was a relic or tribute to the American airmen of the Mighty Eighth in World War II.

Although I'm pleased to say Ruby revelled in the journey, easily settling into fast cruise mode, it was a bit of a squeeze for us. 

We managed with throw-overs and a tank bag. He was sandwiched between a tent on one side (blue package in the pictures above) and our roll mats (black package) on the other. The throwovers were OK but did rub on the rear indicators and it wasn't easy to secure the bungees for the bags without catching the paintwork. So I was really pleased when Tim said he had a rack going spare. 

The rack fixes to four sturdy points on the Triumph's rear subframe. These are all to M8 captive nuts: two intended for the grab rail and two for the tubular steel exhaust/pillion peg hanger.

I'd already made use of the right-hand exhaust hanger to mount my Scott Oiler so wasn't sure if I'd have to relocate it. No problem, as it turned out, because there is actually quite  a lot of space available behind the Mark 1 rear panels. 

Unfortunately, it was not easy to bolt the rack in place because it had to fit over the rear panels, but the rear panels restrict access to the bolt for the exhaust hanger. Nothing that patience couldn't solve but still, it was a fiddly business. 
Access to the retaining bolts was very tight

The rack is now firmly in place and I think it makes a tidy addition to the bike. As ever, beauty is in the eye of the beholder so your opinion may differ.

Wednesday, August 20, 2014

Old shock, new shock

In response to queries on the other thread Trevor (Sprint) confirmed the 17 inch wheelers have a longer shock and here's a photo showing the difference. It's not much but the heave onto the main stand is way less now. With the old shock and the 17 inch wheel it was 2.5 inches off the deck when on the stand now it's just over 1.

Can't say I've noticed a huge change in handling or turn in but the ride quality is much better as you'd expect. Overall a happy chap.

This shows the only difficulty in fitment; I had to relieve the top of the drag link (just chamfered the top edge) to allow the bottom shock mount in as it's more chunky than the original.

Friday, August 8, 2014

Six spoke wheels

I'd borrowed the hollow three spoke Brembo wheels from my Daytona, pending a posh polish and paint job on the original six solid spoke SNW Trophy wheels. Meanwhile, Tim decided he had no use for his six spokers so I thought I'd make use of them (cheers Tim) as a way of returning Streaky his wheels. First off, ditch the 20 year old rubber tubeless valves. For a few pounds, it just isn't worth trusting these critical components. I've seen the front tyre of a bike blow out on a motorway. Not pretty.

Tim's wheels were a bit tired but otherwise in decent condition. I decided to give them a simple tidy up with some steel coloured wheel paint I had for years. Literally. I went for a steel colour because I thought it would pick up the graphite stripe on the Trophy bodywork, rather than the aluminium colour these wheels came in.

After a good scrub with a nylon pad, degreaser and CIF, I could see the paint on the rims was very thin and flaking. So a went over the edges with wet and dry. Also, I treated the inner surface of the rims where they had suffered from tyre irons in the past. 

Tyre iron groove ...
... treated to a foam block and wet and dry ...
... until all is smooth again.
I had some grey primer so treated the wheels to a coat of that to start with.

Unfortunately, there was still some flaky paint around the bare ally on the rim and it didn't take very well. So more rubbing back, more primer - still not great but as I was determined not to agonise over the finish, I went on to the wheel paint.

Not bad ... at a distance

Rubbing back Simoniz steel colour wheel paint as it reacts again

Well, more reaction followed, more rubbing back, more wheel paint. I think they are pretty good now.

I installed a new 160/60ZR18 Avon Storm 2 on the rear wheel ... 

... and then noticed how the inner faces of the swingarm had suffered last winter. So more rubbing back - with steel wool this time - but special metals primer this time. Marvellous. Why didn't I use it on the wheels? No idea other than this time I wasn't thinking about a quick job. I was thinking of a sound one.

As a consequence, the paint took beautifully and no futher rubbing back was required so it was actually quicker anyway. When will I ever learn.

Good as new
With the rear wheel reinstalled, I can see that the rear of the bike sits higher now. Tim discovered that there is a difference in the length of the rear shock absorber for bikes with an 18 inch rear wheel and the later 17 inch rear wheel. That figures, with the difference in stance of my bike, back on a wheel it was originally spec'd for.
Better stance with 18 inch rear wheel and original shocker

I have not yet finished the front wheel but Ruby Trophy 12 is blasting around Somerset and Wiltshire again. Soo smoooth on the new chain and new rear tyre.

Ah,  Summer time

Horrible clonking from my gearbox ... no longer

I had noticed a loud clonking banging noise coming from my gearbox at low speed. This was especially going up hill between 10 and 30 mph. It cleared above 30mph and the rate of clanking was the same regardless of the gear (and hence rev rate) the engine was pulling. That meant whatever it was, it was on the output side of the transmission. Needless to say, I was depressed at what it might mean. Google search suggested a whole range of horrors but - wait - also a suggestion that might just save me.

Apparently, some forum posters had diagnosed a similar problem as nothing more sinister than a worn chain. Internet advice was to check for stiff or frozen links that might be causing the chain to ride up on sprocket teeth, then slap down again to create a banging noise. However, my chain looked great. I put the bike on the centre stand and checked every single joint with two pairs of pliers. All moving smoothly. Clean and well lubricated, courtesy of my Scott Oiler, and no hint of any stiff links.

Comparing standard Trophy (left) and modified Daytona (right) sprocket covers

Daytona sprocket cover with 12mm holes for inspecting gearbox sprocket
I had previously modified my Daytona sprocket cover so I could inspect the gearbox sprocket without draining the oil. At my last oil change, I had drilled three 12mm holes at an appropriate radius the gearbox output shaft. The sprockets showed some clear signs of wear but not particularly worrying, I thought. Then I noticed that the Haynes and Factory workshop manuals quoted a maximum wear limit for the chain as 319mm for a 20 link length. It isn't possible to measure this length along the bottom run of the chain because the exhaust and subframe get in the way. So I removed the chain guard and saw 20 lengths of my chain were at 320mm. Let's say, at the wear limit.

I decided to try a new set of chain and sprockets. The chain was on the bike when I bought it and so has lasted at least the 9500 miles I have covered since obtaining the bike. Who knows how many it had covered beforehand. I decided to make another trip to see Trevor. He offers DID and a cheaper (Triple S) chain options. I so rarely need to change a chain, and in my younger days suffered so often with 'bargain' chains, for me it was a no-brainer to spend a bit more for the fantastic quality of genuine DID.

Contents of a DID VX chain and sprocket kit from Sprint Manufacturing
Trevor also sells Sunsstar gearbox sprockets too - again super quality - and includes a gasket for the sprocket cover and locking tab washer in the kit. All for £140. I was happy with that.

Having split the old chain, by first grinding of the rivet heads and then pressing out the old soft link, I was able to measure the wear on the pivot pin. In the picture above, the wear line is visible but it was less than I had imagined - the step is about 0.2 mm so about 5% of the thickness of the pin. The gearbox sprocket was getting to the end of its life. 

I'm guessing the accumulation of wear on the chain 'stretching' the distance between the pins under load, plus the gearbox sprocket, was allowing the riding  up and dropping of the chain at low speed. At higher speed, the centripetal acceleration could have prevented this as the chain was more uniformly pushed out from the rear sprocket, effectively gripping the gearbox sprocket more firmly. 

Locking tab washer in place

I treated the new Sunsstar sprocket to a dousing of paint because it appeared to be in bare metal. It took quite a bit of jiggling to settle on the splines of the output shaft. It was a really satisfying fit when it went home. Beautiful close tolerance for a part that is under huge pressure in operation. 

DID VX Professional, torqued up gearbox sprocket and
tab washer flattened into place. Perfick. 
I have a chain splitter and riveter kit. It was a bit pricey but rewarding to use with a pricey C&S kit. I measured the external width of the fixed links as 20.5mm so clamped up the soft link to the same degree. The gearbox sprocket nut was then torqued down but selecting first gear, turning the rear wheel against engine compression and standing on the rear brake.

And the result?

No more clonking any more. A result indeed.

Friday, April 18, 2014

What difference do Triumph green camshafts make?

This post starts off with a simple oil leak and ends up with a cam swap from Triumph green profile to blue profile. It means I now have first-hand knowledge of the performance difference between the two, all else being exactly the same.

Shimming the valves

7000 miles later
The oil leak from the cylinder head cover meant I had to remove and reseal it. I was surprised how dirty the cover had become, after having been so careful in my restoration and with the radiator cowls fitted. But that's because it seems like yesterday when I got Ruby back on the road when in reality a year and about 7000 miles have gone by since then.

Central bolts are awkward
I discovered that the cam retaining bolts were barely more than finger tight. I had torqued most of them down on reassembly. I guess the rubber washers under the bolts and large rubber gasket had settled. That was why I had a leak anyway. I was also reminded of how close the central retaining bolts are to the main frame tube. They are impossible to torque down because even my smallest torque wrench won't fit in the gap.

Oil had collected around the plugs
The leak was not just external. I found puddles of oil around the spark plugs where it had run down into the central wells in the cylinder head. These are all blind to the outside world so there is nowhere for any muck or fluids to go if they end up down there.

As I was dealing with the oil leak from my cylinder head cover, I decided to check my valve clearances. I do not have a special tool for swapping shims with the camshafts in situ, though such tools are available for about 60 pounds. I am happy enough to remove and refit my camshafts when the clearances need to be adjusted.

Two of my exhaust valves were out of specification, needing a change from 2.60 to 2.55. With the cams out, changing the shims is easy - lots of room to move and that in itself justifies the effort for me.

Camchain tensioner springs

It is necessary to remove the cam chain tensioner mechanism to get the cams out. I'd also wanted to replace the tensioner spring. Trevor at Sprint has started supplying replacements. The originals weaken over time and so can't make the internal tensioner ratchet take up the slack in the cam chain as Triumph intended. The picture below shows the difference between Trevor's replacment spring and the old spring I took out. It is photographed over the official factory manual with the minimum spring length.
Comparing old (top) and replacement (bottom) cam chain tensioner springs

Swapping T300 Camshafts

Whilst I was at it (famous last words for me) I decided to swap the original 'green' specification camshafts for the later 'blue' specification camshafts. This was just because I could ... the later motor I had bought had these camshafts in good condition and I wanted to try them out.

Blue cam (left) and green cam (right) side-by-side
The blue cams are far far milder - less lift (shorter lobes) and less duration (pointier lobes) as can clearly be seen in the two side-by-side pictures.
Cam Profile Blue Green Red
Inlet open 1 BTDC 21 BTDC 27 BTDC
Inlet close 30 ABDC 50 ABDC 55 ABDC
Inlet duration 211 degrees 251 degrees 262 degrees
Inlet lift 7.1 mm 8.9 mm 9.4 mm
Exhaust open 28 BBDC 51 BBDC 54 BBDC
Exhaust close 2 ATDC 25 ATDC 28 ATDC
Exhaust duration 210 degrees 256 degrees 262 degrees
Exhaust lift 7.0 mm 8.6 mm 9.3 mm
The table above shows cam timing in degrees relative to the extremities of the piston stroke: before top dead centre (BTDC), after top dead centre (ATDC), before bottom dead centre (BBDC) and after bottom dead centre (ABDC). The blue cams have relatively little overlap in period (58 degrees compared to 101 degrees for the green profile) meaning that the exhaust valves close early enough to maximise effect of the charge. The green cams overlap considerably.
Green cam (left) out and blue cam (right) in place

Manual says seal the ends
Plenty of Hylomar around the plug recesses
Finally, I was very careful to seal the cam cover with Hylomar, following the factory instructions. I was confident that this would work because the rubber gaskets have now thoroughly settled and I was more generous with the Hylomar (but still VERY careful) than last time.

So, what difference do blue camshafts make?

I have ridden about 500 miles since installing the blue cams. What difference do they make? A lot. Performance (better below 60mph, worse above) and fuel economy (between 5 and 10% better) have changed.

The engine now pulls solidly from 2000rpm. It is both stronger and linear, whereas previously it would pull but with some hesitation, especially around 2500rpm. The low-rev thrust is a transformation. That is a brilliant improvement. However, the cost as I suspected is that the old kicks at 4000rpm and at 6000rpm have gone. I am not surprised by this after having read contemporary road tests of the original and re-tuned Trophy 1200s.

I can live without the 4000rpm step because it was probably just a sign that cylinder fuelling wasn't working super well below that engine speed. However, the way the engine came on cam at 6000rpm was exhilarating and I miss it. Realistically, I might experience that once or twice on an average ride because the roads around here are not suited to high-rpm riding. But experience cannot be distilled into numbers like 'twice per ride'. I shall be reinstalling the green cams in the next few weeks when I swap the engine covers over for powder coating.

On the other hand, the blue cams make for a much more relaxing and secure riding experience so I have decided to use them in late Autumn and Winter when I think they would suit riding conditions perfectly.

Consequence: I now have two engine tunes available, one for summer and one for winter. Very nice.

Wednesday, April 9, 2014

Red is the colour - Painting a cam cover

Sorting out scabby cylinder head covers

I've been disappointed with my attempts to repaint the original engine covers of my 1991 Trophy 1200. Although I did my very best to strip off all the old paint, I was unable to get every last spec of failed silver paint off of the clutch cover because the casting has some tricky recesses for its retaining bolts. The cylinder head cover (or cam cover, if you prefer) and crank end covers are not as bad but still quite a bit less than nice. Time to do something about it - but how without being off the road?

'No' to being without working wheels; 'no' to scabby covers for Ruby

Dirty scabby sick 2001 engine
Cleaned but no less scabby 2001 engine
The new paint I'd applied to my 1991 Trophy engine has not adhered properly over the old failed paint. Result: new failed paint. Also, the VHT Clear lacquer has gone yellow and started to come away in some places. I used this clear coat over the silver heat resistant paint to get a finish that was close to the original. I now regret trying to repaint this with rattle cans and am going to go for a powder coat instead. However, I don't want to be without my 'triffic Trophy any longer than necessary, especially as the weather has been getting better. So I've been in a quandry about hating the insult of scabby cases that currently adorn my beloved bike and hating the idea of being off the road. Meanwhile, I hadn't done anything with the sick 2001 Trophy engine I'd bought last year, since stripping the top end. So maybe there was a solution here to my quandry?

Borrowed covers

I decided to use the cam, right-hand and left-hand crank engine covers from the 2001 Trophy engine as a temporary measure, plus the clutch cover from by Daytona engine. Yes, another piece of Daytona is temporarily migrating to the Trophy! Even then, the 2001 covers are even more horrible - and would need refurbishing anyway sooner or later. I decided I'd start the process off by working on the cam cover. It is a large casting and, as the picture above shows, had lost a considerable amount of its original black powder coat. I thought it would be a simple matter to shift the rest of it.

Paint stripper is rubbish, wire wheels are harsh and hard work ...

Well I was wrong. I used two types of paint stripper with Scotch abrasive scourers (fancy nylon scrubbers). Despite multiple applications, even leaving the cover in a plastic carrier bag with stripper over night, there were still some patches  that just wouldn't budge. Also, I was left with pitting and quite a number of blotchy dark grey areas in the casting where corrosion had wormed its way into the alloy.
After a lot of work with scourers and paint stripper, most of the powder coat has gone but pits and corrosion remained

In the end I had to resort to a wire brushes and a rotary ginding wheel on a drill and minigrinder (cheap Dremel clone). It took hours. I wouldn't do it again - taking it to a blaster would have been the smart thing to do. Oh well.

Washed down with degreaser
Belt sanding ribs
Ultimately, I was pleased with the finish I obtained although to get rid of pitting I had to remove quite a lot of aluminium from the ribbing that runs across the top. I used a belt sander for that - very harsh but much more helpful than a rotary wheel for keeping the surface flat. A good wash down with degreaser and I was content to get the paint out again. This time, I decided to go red because I had a can in my garage and, as a spare, I am looking at the 2001 engine as an opportunity to experiment some more.

Shiney Red Cylinder Head Cover: Mission Accomplished

After the first coat of red, I could see that the dark grey areas were not covering over very well. I had a tin of VHT Black so I gave the cover a blow over with that as an even colour  - like a primer - to work with and then started again with the red. This time, the red enamel was covering evenly. I built up the coverage in thin layers, each time using a hot air drier to partially cure the paint as I went.

Finally, I decided to use up the last of my VHT Clear. Yes, the same lacquer that had failed on my other covers, Clear lacquer makes such a difference to solid colours I thought I'd risk it. Also, if it does yellow, the effect will be less noticeable over red than over silver. We'll see. 

Red enamel and VHT Clear - a bit of fun
The result looks good to me for now. So I'm ready to swap the cam cover over, maybe this weekend, and to take the originals to a local coater.