V7 tyre fitting, part 2 – 16 Nov 2017.

And so to the front wheel. I repositioned the support and tie-downs which always takes me a bit of time. I’ve seen photos of bikes which have taken a tumble from benches like mine.

Once I was happy, I removed part of the bench wheel clamp, jacked up the front end and set about removing the wheel.

It’s easy enough. I have to remove the mount I made for the push bike speedo sensor first. Then disconnect the brake cable and start by removing it from the handlebar lever first. The other end can then be removed from the lever on the hub. The spindle/axle nut is undone and the clamp bolts at the bottom of the forks are slackened off. The big old screwdriver is then employed to wiggle the wheel spindle out. Usually the hub cover plate drops out with a clang at this point as I forget it’ll do this. I had to raise the front of the bike a bit further before the wheel would drop out because there wasn’t quite enough room for the brake plate to clear its locating plate on the fork leg.

Once it was out I went through the same performance as I did the other day to change the tyre. The old tyre was difficult. The new tyre was easy. Here is the newly mounted tyre next to the old ‘un.

The size difference is quite noticeable even though the widths are much the same. The 90% aspect ratio of the old tyre means its diameter is actually 20mm less than the new one.

I balanced the wheel which only needed 10g. I reused a real lead weight using some good double-sided tape. I would like to use spoke weights rather than these stick-on ones. I’ve seen some for sale but want to get proper lead ones if I can.

As they say in the manuals, “refitting is the reverse sequence to removal” (but you might swear in different places). Here’s the new tyre fitted.

I fitted the wheel clamp back to the bench

then turned my attention to another little job. Back in the summer, the loop securing the front brake cable to the mudguard broke and I just taped the loose bit up and out of the way. I needed to fabricate a new one which was surprisingly difficult. It will do until I can find something better. You can see in this photo where the cable has rubbed the paint of the edge of the mudguard.

There was now the thorny issue of tyre pressures. Originally Moto Guzzi specified 21psi in the front and 25 psi at the back for solo use with the rear to be increased to 28psi when carrying a pillion. The handbook also says to add about 3psi to the pressures if doing constant high speeds.

I was running the previous tyres at higher pressures (32/36psi). I’d been told this was necessary with more modern tyres. In fact, some said this was still on the low side. The issue I now have is that the maximum pressure for the new Mitas tyres is 33psi. The old Michelin rear tyre had the same load rating but carried it at 41psi.

Even so, the original “book” pressures still seem very low to me so, in the absence of anything else, I’ve gone with 24/28psi as a starting point – the “book” high speed/motorway pressures. I’ll see how it goes and might contact Mitas UK to see if they have any thoughts.

Here’s the fire bike ready for a run to scrub the tyres a bit. It was dry if a little cold.

It was only a dry test but, so far so good. I can notice a slight change in that the steering seems heavier at very low speeds, say under 10mph. Once rolling traction and grip seem more than adequate and the handling just as it was before. I doubt I’ll have to wait long for the chance to test wet weather performance!

Oh, one thing. The increase in front tyre size has made all the difference when putting the bike on the centre stand. I’d been finding this hard going to the extent that I avoided it. Now I think about it, the side stand didn’t ground when I took the bike off the bench like it had when I rolled it up there.

The annoying squeak from the front suspension is back but I know what the cause is. It’s the front brake cable rubbing as it passes through the support loop and grommet!

Once back in the garage there was one last thing. I recalibrated the push-bike speedo for the new tyre size and fitted a new magnet. I’d knocked the old one off during the tyre change. It got a bit messy as I had to cut the tube of Stixall open to find the last useable drop!

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V7 tyre fitting, part 1 – 13 Nov 2017.

I got my tyres after some unnecessary shenanigans. I was let down by the first suppler who accepted my money then contacted me a day later to say the tyres weren’t in stock so they were going to give me a credit. I checked their website and, lo and behold, the tyres were still listed but had gone up in price. I considered this to be sharp practice and told them so. It meant that I could actually get the tyres elsewhere for less than their new price so, that’s what I did and insisted on a refund. I wasn’t bothered by a 4-day delivery time. It took 2 days for the original company’s accounts department to process the refund which then took several days to reach my account. To top it off they asked for my feedback on resolving the issue before I’d even got my money back. I told them what I thought again. Oh, and I promised I’d give them a mention here so, Pneus Online you get a definite thumbs down from me.

Now I’ve got that off my chest let’s get back to the task in hand. As the rear tyre was pretty near bald I decided to tackle that one first. Here’s my tyre changing kit. Tyre levers, bead buddy, valve core remover, rim protectors, tyre lubricant and powder to stop the tube sticking to the tyre. The thing with the yellow string is a home made tool that screws into the valve stem to pull it through the rim. I’ll buy the proper job when I see one. Also on hand was the garden spade. More of that later.

I’m not going through the process of changing a tyre as there are plenty of helpful videos on you tube. This time I’m going to try and get the rear wheel out without having to remove the exhaust. I’m lucky in having a lifting bench with a trap door which should allow the rear wheel to be dropped clear. I managed to get the bike secure on the bench without having to call for assistance.

Ground clearance was an issue when I wheeled the bike onto the bench. The “washer” welded to the side stand caught on the bench top as it went over the crest.

The one thing I did take off was the left hand pannier to give me access to the brake rod etc.

You can see here that, if I want to drop the wheel completely through the hole in the workbench, the ramp will get in the way.

That ramp was soon off.

Now to actually get that wheel off. I’m sure I’ve described this before but never mind. First thing is to disconnect the brake pull rod from the brake hub by undoing the knurled adjuster.

Then the brake torque arm has to be disconnected as well by removing this nut. The fixing at the other end to the swing arm has to be slackened as well before it will come off and that end is difficult to get at with a non-flexible wrist like mine.

I then remove the spindle/axle securing nut before undoing the clamp bolt on the swing arm shown here. I use a big old screwdriver to get everything moving.

Before pulling the spindle out I removed the plate from the bench but put a bit of timber across the gap until I was ready just in case.

The spindle now comes out but I hold the wheel and brake hub against the drive box while turning the brake plate so that no nuts can catch when I pull the wheel toward me off the splines to lower it away from the bike.

I came across a problem at this point. I found that the complete wheel assembly was too heavy for me to manage and, having come this far, I had to come up with a solution quick smart. I decided that, with that bit of wood holding the tyre up, I would lower the bench halfway so that I could drop the wheel through the trapdoor and against the frame of the bench. I was able to take the brake hub off before jacking the bench back up a little at a time until the wheel was free. Where there’s a will…

The actual changing of the tyre was interesting! It was an absolute fight to get the old Michelin tyre off. Breaking the beads was easy enough. I did it the way I always have using the garden spade and jumping on it! After that I spent ages. I could get the first bead over the rim but the second one didn’t want to play. In the end I took both beads off so the wheel fell down inside the tyre. I then had to rip the wheel out from the middle which took all my strength. However I did it without causing any damage to the rim or me. I wasn’t pleased to find that the new tube I had given the tyre fitter (I wasn’t able to do the job myself following my broken wrist) had 2 patches on it. He’d obviously had some issues then! I cleaned up the rim and fitted my new tyre. How easy was that? Only one lever was needed to get the first bead on and two for the second one. There was no heavy levering needed and it was safe to dispense with the rim protectors. Perhaps it’s because these are tube type tyres and the old ones were tubeless but used with tubes. I don’t know but, this is how I remember it used to be.

I got my home made tyre balancer out and was pleased to find I only needed 30g of weights. The old tyre had a lot more than that.

Here are old and new. The new tyre looks a bit wider but isn’t. It’s just because that one’s mounted on the wheel.

While the brake plate was off I checked the linings. They are still good (4mm). I had begun to wonder because I had run out of adjustment on the brake pull rod.

Much to my surprise getting the wheel and brake plate back on the bike was easy enough. I was able to stand behind the bike, reach through the bench and lift the wheel up so I could shove that bit of wood under again. Maybe I could use this technique to get the wheel out next time. So with the wheel back on the drive splines the wheel spindle was put back in place. The brake torque arm needs to go back on before tightening the spindle nut, then the clamp bolt on the swing arm.

As I’d run out of brake adjustment I decide to move the lever on the brake plate. I marked it’s current position before removing.

Then I refitted it turned one spline.

The brake rod was then refitted but to do this I had to lever the arm round a bit first so that I could get everything properly located.

Now I was able to adjust the brake to give about 10mm free play at the pedal and with the bike back together I reassembled my bench.

Front wheel next time. That’ll be easier, right?

The hunt for tyres (again) – 1 Nov 2017

It’s been a strange sort of year for me and, although I’ve managed to attend my usual camping and rally weekends throughout the summer, it’s been more through good luck than anything else. Toward the end of the summer family business has meant me traveling from one side of the UK to the other every week or so in the car. This actually meant that I didn’t have time to arrange an MOT in time and the Fire Bike had to be taken off the road for a month. When I did eventually take it in for the test it did pass but, only just! I was given two “advisories”. One for each of the tyres. To be fair the rear tyre was so worn that it could have been failed while the front tyre was just about ok.

I was disappointed that both tyres were so bad. My records show that I’ve done 9732 km on this set of tyres (6082 miles). I realise that many bikes wear their tyres out as quickly if not more quickly than this. Now, the V7 700 is a heavy old beast but it’s hardly powerful and is ridden pretty conservatively. I decided that this time I would try a more traditional tyre in the original 4.00-18 size front and back. Previously I had gone with more modern sticky tyres and a low profile size on the front (see here) when I settled on Michelin Pilot Activs. I already knew that there aren’t many 4 inch front tyres available in the UK so, when I made my list it was a short one.

I cast around for opinions. Some thought that I was just wanting tyres that look in keeping with 45 year-old a bike and there would be a trade off with performance. As it happens, all the tyres available bar one (Heidenau K36) are of an older block style. I wanted feedback on other people’s experiences with these tyres on a loopframe Guzzi. Those who used them said they were fine. This is much what I would have expected as it’s what the bike was designed to run on.

In the end I decided to go with a pair of Mitas H06 tyres. There were a number of reasons. Firstly they were cheap! However, the feedback I got from people running these tyres, albeit on different models of bike and in different sizes, was always positive. I figured that, if they didn’t last well, I wouldn’t mind at the low price and I was assured that I wouldn’t be taking my life in my hands riding on them. We’ll see!

Modified trailer wiring – 10 May 2017.

Here’s another “late” post!

I have been having some trouble with the electrical connection between The Fire Bike and my trailer. I’ve changed both the plug on the trailer and the socket on the bike but can’t get things to stay connected properly. The connection is too loose causing me to lose lights on the trailer. I decided that I would do away with the trailer socket on the bike and use the 5-way superseal connector I had fitted for the top box lights. Recently this has become pretty much redundant.

I traced the wiring on the trailer to check out what does what before wiring in the other half of the superseal connector. Although all 7 wires of the trailer plug were wired up one wasn’t connected to anything and two others were joined together so only one of them was needed.

Original socket;

  1. Yellow “L” – LH indicator.
  2. Blue “54g” – Fog lamp (not used).
  3. White “31” – Earth/ground.
  4. Green “R” – RH indicator.
  5. Brown “58R” – RH tail but connected to both tail lamps.
  6. Red “54” – Brake lights.
  7. Black “58L” – LH tail but connected to both tail lamps.

I therefore cut back and insulated the ends of the blue and black cables as they won’t be reused. It was then easy to fit the other half of the superseal connector to the trailer, or you would have thought so! I made a note of the numbered connections to the half already on the bike then wired the trailer the same, but that’s just too easy. The two halves are each numbered 1 to 5 alright, but in reverse order to each other! Once that was sorted all worked as it should.

Here are the old and new plugs with a blanked off socket to keep the weather out when it’s disconnected.

And connected up. When not in use the cable end is clipped up to the indicator bracket as it was before. In use it’s clipped to the tow bracket.

I’ve used the trailer twice since making this modification with complete success.

Fuel starvation? – 4 May 2017.

It’s taken me a while to get around to writing this post. Other stuff has been going on!

On a couple of occasions recently The Fire Bike has come to a halt without any prior warning. I’d be riding normally and the bike would appear to run out of fuel. It would be just as if I needed to switch over to “reserve”. However there was plenty of fuel in the tank. The first time it happened, I had refuelled and the bike faded about 40 miles later. I pulled over suspecting a vacuum in the tank and opened the filler cap but there was no sound of air rushing in. The bike then ran without any problem for the remaining 50 miles or so home. On the second occasion I had ridden the 20 miles to Aberystwyth seafront where there was a MAG gathering. After an hour or so I left to call at some shops nearby then set off for home. After about 5 or 6 miles the bike ran out of steam again. Again I opened the fuel filler but heard nothing. The bike restarted and I carried on the rest of the way home as if nothing had happened.

I hate it when things like this happen and the fault can’t be recreated in the workshop.

General opinion amongst fellow Guzzisti supported my initial thoughts that the problem was caused by fuel starvation with a second possibility that the ignition coil was beginning to break down when hot. The brief stop being long enough for it to recover. I ordered a replacement coil, just in case, but decided to check the fuel system from tank to carbs and the ignition wiring.

Before doing that, I thought I would just see if I could get the fuel supply to the carbs to fail. I made sure there was a decent amount of fuel in the tank and that the cap was done up tight. I then disconnected the fuel line from the running tap (as opposed to reserve) and added a short hose into my fuel can. I turned the fuel on and watched as it all ran out! I had hoped that the flow would reduce until it stopped or sucked air up the pipe proving that the filler cap was blocked. However it all ran out unimpeded.

The next step was remove the tank so I could make my checks but, first the seat needs to come off.

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Now the tank itself can be removed.

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  • Electrical connections in the battery compartment. Especially earths. All good.
  • Connections at the coil. These were fine.
  • Connections to ignition switch. All good.
  • I rattled the key in the ignition switch but couldn’t make it fail.
  • Fuel lines. All clear.
  • Fuel taps and filters. Fine.
  • Fuel filters at carbs. Clear.

I went back to the fuel tank which was sitting on my bench in the sun. When I opened the filler cap I quietly swore as I heard it exhale! If the expansion caused by the tank getting warm can’t be vented then neither can air get in to replace the fuel as it’s used up. So, after going around the houses, I was back at my first suspicion that the fuel cap was the problem. This is despite the fact that the bike has run without any problem for the last 2 years.

I had always suspected the cap because, way back, I had puzzled about how it was vented. There were two small holes outside the area covered by the rubber seal but no corresponding vent hole inside the seal that I could find. I drilled a 2mm hole in the inner layer of the fuel cap where I would have expected to find a vent hole. In this picture you can see my newly drilled hole and the outer two holes to the left and right of the rubber seal.

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To test it out, I squirted some WD40 into the hole I had drilled and saw it come out of the other two. I then washed it out in petrol and refitted it.

Before I refitted the tank I straightened out the rear mounting flanges. They had been crushed a bit. I had bought a stainless steel rear tank mounting bolt a year or so back so this was fitted as well. The old one was pretty nasty.

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I haven’t got a replacement front bolt yet. This is a stepped bolt which prevents it being over-tightened and could be something to make on the little old lathe I’ve bought. It’s just about set up now.

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Anyway, Everything went back together and a few days later I managed to complete a 55 mile test ride without any sign of trouble. Time will tell if I’ve really solved the issue.

I never did fit the replacement for what is probably a 45-year old ignition coil. It arrived damaged and was returned but I haven’t bought another. I wouldn’t have fitted it anyway until I was sure it wasn’t a fuel issue.

Too many volts! – 11 Mar 2017

I’ve mentioned before that, over the last few months, the voltage warning light on The Fire Bike has been “playing about”. I fitted this soon after getting the bike so that I will know if the charging system develops a fault and can do something before I get stranded with a flat battery. I have said that the light had flashed red on one occasion indicating low voltage. Well more recently it was flashing alternate green and red which indicates an over-voltage (more than 15.2V). It may be that this was what was happening the first time but I just couldn’t see the green colour in the sunlight. Anyway, an over-voltage is to be avoided because it will soon kill the battery.

My bike has a Magneti Marelli dynamo and mechanical control box. The original fitment. I consulted with my friends on the Guzziriders forum as there is a thread there about fitting a solid state control box/voltage regulator sold as a replacement for an old Fiat. Someone had bought one from Teo Lammers but they are currently out of stock. It’s here. I decided to see if I could find one at a classic Fiat specialist here in the UK and managed to get one from Motobambino. I thought the price was good and it arrived inside 24 hours.

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There was some discussion on the forum about the current rating of the solid state regulator. The original mechanical box was rated at 25A and this replacement at 16A. The dynamo is also 25A. So far as I can tell, a 16A regulator with a 25A dynamo will work fine but, the output (current draw) is limited to the 16A of the regulator. I’ve done some searching and it looks like the Fiats had a 230W charging system as opposed to the Guzzi’s 300W. However the two systems seem to have had their ratings worked out differently.
– Fiat – 14.5V x 16A = 232W.
– Guzzi – 12V x 25A = 300W.

The lowered capacity of the system could cause issues on an original police bike running radio, siren, blue lights and other stuff but, should be fine for my “civilianised” one. I’ve used a “worst case scenario” of 12V x 16A which gives a maximum system capacity of 192W. I think my maximum constant draw is about;
– Lights (bike) – 75W
– Lights (trailer) – 10W
This leaves plenty for the ignition circuit. The intermittent draw from starter, indicators, horn and the like can be disregarded. I might have to think again if I add heated grips or stuff like that.

Changing the control box.

I removed the battery and, before I did anything else, photographed the original mechanical box in situ and made a note of all the connections.

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I disconnected the wires and undid the nuts securing the box to its bracket but I couldn’t shift it! The two bolts were too tight in the mountings and appeared to need to be unscrewed from the back. To get to the first bolt I removed the nuts and bolts securing the left hand tool box which released the mounting bracket for the control box on that side.

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I then realised that I didn’t actually need to take the tool boxes right off. I could just remove the top fixing.

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This done you have access to the back of the bracket. Here the bracket is fully floating and the old Marelli box has been removed.

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The mountings for the box weren’t threaded. Just tight and the screws had to be wound out.

Here are the two control boxes for comparison.

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The mounting holes are at the correct centres but needed to be drilled out. There was also an earth/ground terminal on the original. I found this area could be drilled to accept a terminal while still clearing the mounting bracket.

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Being a mechanical device, the old box had mountings to protect it from vibration. These are not removable.

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I don’t think these are strictly necessary for the solid state replacement but I punched some bigger holes in some rubber washers and used them to mount the plate. You’ll notice that I filed all the corners off that plate. Twas flippin’ sharp.

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You can see in the photos that the wiring connections were in the same order as on the original. I had to do some checking in my manuals to make sure this was the case as the terminology on the two boxes was (of course) not the same.
– Marelli box.              “D+ 61”  – “DF”      – “51 B”.
– Replacement box.   “51”        – “67”       – “30 +12V”.
– Guzzi manual says. “D+/51” – “DF/67” – “30/B+”.
This is the illustration from the V7 workshop manual which explains things.

Marelli Regulator Unit

With everything back together again the bike was restarted. All seemed good then it stalled. Once I’d turned the fuel on all was well!

Today I’ve been out for a test ride. Just the 20 miles up the A487 to Aberystwyth for coffee and cake on the sea front then back home. I have to say that the new regulator is an improvement. The strange messages given by my voltage light have stopped. Not only that, the light turns green (signifying normal charging) at lower engine revs than before. This means I don’t have to change down to keep it “in the green” and can potter about in a lower gear.

I have had a look inside the old control box which is clean with no obvious faults. Interesting.

Re-torque heads and adjust valve clearances – 22 Feb 2017

I’ve now ridden about 230 miles since doing the work to change the cylinder head gaskets on The Fire Bike so, it’s time to retighten the six nuts securing each head and barrel. I like to do this around the 200, 500 and 800 mile mark. That’s about 320, 800 and 1290 Km.

Before doing anything, I wanted to check something out. My Moto Guzzi factory manual for the V7 700 and 750 models and the Chiltons’ Manual both quote the torque figure for the nuts as 27.5ft.lb (3.8Kg/m). This just feels a bit low. I checked the Guzzi factory manual for my V7Sport and this quotes 29 to 32ft.lb (4 to 4.5Kg/m) for the same fixings. They’re basically the same engine so I thought I’d get some advice from members of the Loopframe Guzzi Group. The consensus was that I should use 32ft.lb (4.5Kg/m) and, given the size of the fixings this makes more sense to me. So, on to the job in hand.

The first thing I do is remove the dynamo belt cover and the spark plugs so that I can turn the engine over with a 26mm spanner or socket. The engine rotates clockwise seen from the front.

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I started with the right hand side and removed the rocker cover. Turn the engine (clockwise) with something resting on the piston to tell when the piston is at the top of its stroke. If the rockers are loose then it’s on the compression stroke which is what you want. If not turn the engine till the piston comes to the top again.

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Once you’re sure you’ve got the piston at the top and both valves shut work can begin. A word of warning. Be careful what you rest on the top of the piston. You don’t want to get anything jammed in there or to damage the piston or spark plug hole. I used a long Allen key this time.

The reason I find this setting is so that there is no pressure on the valve gear when I remove the rockers and shafts to access the cylinder head nuts. I would have to do it later anyway to set the valve (tappet) clearances.

To remove each rocker you have to take out the locating screw.

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Then slide out the shaft.

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Above each rocker there’s a spring and washer.

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Keep the sets of components together and put them to one side. The pushrods can be left where they are.

Remove the 26mm blanking plug over the sleeve-nut at the top then slacken the 6 nuts just a quarter turn.

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Do this in the reverse of the diagonal tightening sequence. So

  • Top (10mm Allen sleeve-nut).
  • Bottom (below spark plug).
  • Bottom right.
  • Top left.
  • Bottom left.
  • Top right.

Now get the torque wrench out, set it and do them all up again. This time the order is

  • Top right.
  • Bottom left.
  • Top left.
  • Bottom right.
  • Bottom.
  • Top.

Check the state of its crush washer then replace the 26mm blanking plug.

The rocker gear can go back on now. Often the adjusters have to be slackened off a bit because, having tightened everything down, the gaskets have been compressed a bit more and reduced the clearances.

Adjusting the valve clearances.

Before going any further, I always re-check that the piston is at the top of its compression stroke. I generally turn the engine backwards a little way then forward again while checking for the top of the stroke with a rod again.

Settings are 0.15mm inlet and 0.25mm exhaust.

Use a feeler gauge between the face of the rocker and the valve stem to check the gap and adjust this by turning the top of the adjuster with a slotted tool and locking it in place with the nut on the adjuster. You’re looking for a snug, sliding fit. It should be possible to remove the gauge and then reinsert it. If the feeler gauge is gripped then the gap is too tight.

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Often tightening the lock-nut will mess things up. I never seem to get it right first go!

With the rocker cover back on I can turn my attention to the other side then finally replace the belt cover and put the plugs back in.

Other stuff.

I don’t know what was going on with my voltage warning light the other day as it’s now working properly again! All the same, one day I’ll wire it via a relay because it’s always been affected by a voltage drop across the ignition switch contacts.

I’ve got to paint that ding in the tank. I’ll probably just use a small brush to fill in the damage.

My V7Sport needs an MOT test but I might leave it for a week or two so that it comes around each March instead of every February.

I did manage to get hold of a small lathe and have been spending a bit of time cleaning it up and sorting out the motor arrangement. It came with a big but slightly wobbly home-made metal stand which I shan’t be using. I’ll make something more suitable with some second-hand timber salvaged from some work I’ve just done on the house. My friend, Bunny, has been busy producing stuff for it on his bigger lathe.

It’s not been a bad Winter but Spring will be here soon, the roads will be free of salt and the riding, camping and show season will be upon us.