Sunday, 21 July 2019

SV 650 Valve Clearance Check & Adjustment

Here I'm doing a maintenance task that I was really not looking forward to.

The SV's engine has many virtues. It's slim, powerful, torquey and smooth but maintenance is a bit tricky. I've ridden the SV for 20,000 miles and a valve clearance check was overdue.

The engine is a double overhead camshaft design with four valves per cylinder. Valve adjustment is by shims under buckets. This is the same as my CBF (My FJ has shims over buckets which makes things much easier) I've adjusted bikes with this arrangement and it's ok so long as you're comfortable about taking engines apart - the camshaft needs to be removed to if you have to replace the shims. 
Shim under & over bucket

The problem with the SV is access. The front cylinder head is obscured by the radiator and the rear cylinder lives deep inside the frame. I think that checking the gaps should be straightforward but adjustment less so. When you remove the cams you have to remove the cam chain tensioner and access seems tricky. 
 
Looks tight. Note radiator with flaking paint.
I watched some YouTube videos about checking & adjusting the valves. If these guys can do it, so can I.


I bought a new set of feeler gauges
It was reasonably easy to get to the valves



The measured clearances
mmmm. All the valves are tight or at the low end of the specified clearances. I'm going to have to do a bit more work.

You might be surprised that the clearances are on the low side. You might assume that clearances would tend to get larger due to wear on the camshaft and followers. But I think in modern engines with good oil the rate of wear is negligible. What happens is that the valve bashes it way into the head (very slightly) thus reducing the gap. 


I removed the airbox to get acces to.....

The cam chain tensioner.

I found a guide on the web and it turns out you don't have to remove the tensioner. You can remove the spring and release the ratchet that prevents the plunger retracting.
    
Tensioner spring & bolt


I'm starting with the front cylinder. I've removed the cams, buckets and shims. Note duster to prevent anything falling into the engine.
The shims have their size marked on them but this has been mostly worn off. I use a micrometer to measure them.

My calculation sheet. (dimensions in 1/100 mm) Here I work out what shim to fit to get the correct clearance. The valves that are in spec but near the lower limit will get a shim one size (0.05mm smaller) this will bring them into the middle of the range. I'm do this because it will hopefully mean that they are less likely to go out of spec in the future.

I'm swapping all four shims but only have to buy two since the two from the exhaust valves can be used on the inlet valves.

At this point you might expect me to do the rear cylinder. But its checked with the crankshaft in a different position and I'm loath to turn the engine with the cams out. I'll wait until I've got & fitted the new shims before working on the rear. This makes the job slower but I think worth it. 

I got a pair of new shims and installed them. The existing shims from the exhaust valves went into the inlets and I put things back together. I checked the clearance and they're all now in spec.  


The rear cylinder is a repeat of the front cylinder. This time the tensioner bolt is hidden behind the frame. I removed the footrest hangers and I can get to the bolt by feel.

As with the front, two of the clearances were tight and two were on the low end of the spec range. Again I decided to put in shims two sizes smaller (0.10mm) into the valves out of spec and one size smaller (0.05mm) in those on the bottom end of the range to get them in the middle of the range.  

A tip I got from a Youtube video was to zip tie the cam chain to the can sprockets to keep the timing from going out.
Again I ended up with a set of valves with in-spec clearances. I now put everything back together and I'm good to go.
I sprayed the radiator before re-fitting
The bike is all back together and running fine. The next check is in 15,000 miles or about 3 years of riding. Experience tells me that once set the clearances are likely to stay in spec. The job was a bit of work but not as bad as I had feared.

Wednesday, 17 July 2019

A Viewpoint with Something Missing

And it's something pretty important…. a view.

On my way to Kinloch Hourn I rode a few miles past my turn-off to see one of the finest views in Scotland from the viewpoint at Glengarry. There is a stunning vista westwards along Loch Garry to the mountains beyond.

I say "is" when I should say "was".  
 
The view on Monday

The view in May 1997 en route to the MZRC Rally at Applecross on my Saxon
There was a constant stream of tourists stopping and looking distinctly underwhelmed. I explained to a couple of foreign woman that they used to be a great view here…20 years ago.

Someone really needs to get busy with a chainsaw.

Monday, 15 July 2019

Road to Nowhere

 Or "Far from the Madding Crowd" Highland style. 

I'm always looking for a new road to ride particularly one with a novel feature. Here I'm riding Britain's longest dead-end road.

It's in the West Highlands and runs from Loch Garry westwards to Kinloch Hourn.

The single track road leaves the main road north of Inverness and runs 22 miles past Loch Garry and Loch Quoich to Loch Hourn. I usually avoid the West Highlands in high summer because the roads are jammed with tourists. I was searching for solitude & great scenery….and I wasn't disappointed.   
The route

Loch Garry

Hub cap collection

The road is narrow and winding but almost devoid of traffic

Loch Garry

When I thinking about this trip a couple of months ago I found that the road had been blocked by a landslide. It must have been here at the Loch Quoich Dam. You can see that the entire hillside collapsed.

There was a new bridge at the foot of the slide - I guess the old one was destroyed.



River Garry

Loch Quoich at the dam

Loch Quoich looked spectacular





  




At was near the end of the road…..
….when my way was blocked by these fellows

Kinloch Hourn is just a couple of houses
 
I got past them and the road turned into a narrow track. The loch meets the sea 12 miles west of here

The old FJ may have many years & miles behind it but it's still going well


Sunday, 14 July 2019

Nanna's Bench

On a farm road outside Kilbirnie in Ayrshire today I came across this charming memorial bench. It was surrounded by well-tended flower boxes.





The view

Thursday, 4 July 2019

Borders Run on the FJ

After fixing its leaking fork the FJ passed its MOT (annual safety check) This allowed me to do some overdue maintenance on the SV (details to follow)

I took the big beast for a run to the Scottish Borders. It is strange riding the FJ even after a break of only a couple of months. Compared to the SV it's heavy but comfortable and an effortless high speed cruiser.


Horses graze beside the River Clyde at Thankerton

Whiteadder Water just over the border in England

Berwick upon Tweed - Berwick Road Bridge with the Royal Border Railway Bridge in the background

The Old Bridge (1634)

Kirkhope Tower near Ettrickbridge. Described by Wikipedia as "remote and austere". Now a private home. Early 16th century.



Yarrow Valley

Sunday, 30 June 2019

FJ Fork Seal Replacement


I recently noticed a small leak on one of the FJ's forks. The bike's MOT (annual safety check) was due so I decided to replace the seal. This is fairly simple job and one I've done in the past. A couple of special tools are needed though. From my records I see that the seal was last replaced 8 years and 55,000 miles ago so not bad.   
 
The leak is very slight but I guess it won't get better

Tip - loosen the fork top bolt before removing the fork otherwise it's tricky to get off

Fork removed

Drain oil

This is the dust seal

The metal inside the seal has corroded and burst the seal. I don't think this caused the leak but it's not good because flakes of rust could score the fork leg.

I got a pair of oil seal & a pair of dust seals

To strip the forks a special tool is needed. It's a long bar with a 27mm hex head. I made this one years ago.

It goes down the fork to allow the damper screw to be removed

The fork then comes apart

There is some pitting on the fork leg

The pits are outwith the stroke of the seal (otherwise the tube would be scrap) I buff them smooth to avoid damaging the new seal when fitting.

New seal installed

To push the seal into place I made this tool a long time ago

New oil

The dust seal on the other fork was a bit crusty so I replaced it as well

All done. The fork protectors are after market. I don't know if they do any good but why not?