A sticking rear brake – 1 Nov 2018.

A few days back I described how the back brake on The V7 700 Fire Bike was sticking on. If I used the brake the pedal would stay down, the brake light stayed on and the brake would drag. Today I had the chance to take a look at this. I also took a look at the gearbox leak on the V7Sport but will have to report on that later as I’m waiting for a replacement part.

I was fairly sure that the problem was within the rear brake drum so removed the left hand pannier to get at it. I disconnected the brake linkage from the drum.

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I was surprised to find that I was wrong and it was actually the brake pedal pivot on the frame that was causing the stiction.

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I removed the pinch bolt then tried to remove the lever. I had to spread it a bit but found that it still wouldn’t come off because the footpeg was in the way. It’s pretty tight between the starter motor and footpeg.

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I considered removing the foot rest but this appears to be quite a job. The bracket is held by the bolt which mounts the gearbox to the frame and by a couple of smaller ones to the leg shield. That big bolt will be hard to loosen as the exhaust pipes make access difficult. I am concerned that it is frozen in place. Idealy the engine and gearbox mounting bolts should be turned from time to time to ensure they stay free or, perhaps better, should be replaced with stainless steel copies. Anyway, I decided I would give this prospect a miss. I checked my manuals and parts books and saw that there is no reason why it shouldn’t be possible to knock the pivot back a little through its bracket. You can’t bash it right out because there are plenty of other parts in the way.

I spent a long time squirting dismantling fluid at it and wiggling the pedal up and down. Eventually I thought it was free enough to attempt driving it back through the pedal with a drift. I managed to get it to go back a few millimetres but that was all the clearance I needed to get the brake pedal off the shaft.

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I refitted the lever at a diferent angle and continued to try and work the shaft free but eventually resorted to carefully heating the end of the shaft with the fine burner on my blowlamp.

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I surprised myself and managed to do this without lifting the paint from the frame. Once it was good and hot I doused it with penetrating fluid and produced large amounts of smoke. A wiggle confirmed that it was a bit better and the process repeated with more improvement.

The spindle was brought back through the frame mounting and the job done again. I was happy that it was now freed off but it had to be knocked back once more so that I could get the pedal back on

Once all together I was able to confirm that the problem is fixed, at least for now, and I can ride the thing. At some point this will all have to come apart for that shaft to be properly greased. I don’t want to just rely on WD40 as a lubricant. However, it will have to do for now. I can also foresee hours of entertainment moving that gearbox mounting bolt and possibly the front engine bolt as well. I should have known better and removed and lubricated them before. Ho hum.

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So what happened? 17 Jun 2018.

I realise that it’s been over 6 months since I posted anything! I can’t say this has been because of anything specific. There’s just been lots of other stuff to do. I did virtually nothing in the workshop for months and rarely got out on two wheels which is just not like me. Looking back over 2017, things were busy but not on the ‘bike front. The Racing Rhino was put away over the winter with a coat of ACF50 and the Fire Bike only used occasionally during that time. The salt doesn’t seem to have done it much harm.

My personal injury claim following the accident in September 2014, when the S3 was wrecked, is still unresolved and I’ve just been given a date in January 2019 for a Court hearing. There’s still some chance it will be sorted out without needing to go to Court. At the end of May 2017, I had a further operation on my damaged wrist when all the metalwork was removed. It was done while I was awake. It didn’t hurt but I wouldn’t have minded missing the experience. Despite this the aches and pains are getting worse and the constant need to find work-arounds to get things done is becoming a drag. I forgot to say that the other side finally got around to admitting liability in May last year for the crash more than two and a half years after the event.

I never did get any further with making the tow hitch for the V7Sport. To be honest, I’m struggling with my welding at the moment. I seem to have lost my touch with both my MIG and arc welders. I still intend to complete the job but first I’ve got to get some practice in.

I’m just getting back to spending my usual time in the workshop. There have only been minor jobs to get done. The V7Sport had its MOT test in April and I see that I’ve only managed to do 650 miles since the last one.

We’ve been having a good summer so far and I’ve been getting out more and more to local bike nights and MGCGB meets. I exhibited the Fire Bike at a local show and went away last weekend on it with my mate to The Back to Basics Historic Bike Camp which was held in Essex this year.

Reading back that all seems a bit glum but I’m ok! Hopefully normal service will be resumed shortly.

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!