Its been a while since I’ve been out on the CRM but this weekend was the local TRF’s bikes, bevvies and banter weekend, camping in a field near Hexham so I made the effort to go along.
Friday was intermittent rain but it was not raining as I arrived, got the bike out the van and put the tent up. It stayed dry through most of the evening and the campfires were great for keeping warm. There was also a projector, a screen made from bits of wood and an old marquee and some of Steve’s on bike camera footage on display when it got dark enough. When the rain did arrive it was time for bed. It was also rather cold overnight getting near freezing. It rained all night and was raining the next morning.
I was in a group of 5 bikes in the ‘oh look nice scenery’ group which was being led by the treasurer and the three others were southern foreigners. We left a bit late in the hope it would fair up as promised. The bike started first kick despite being in the rain all night which was a surprise. At the first gate I stopped for, it wouldn’t restart and I ended up bumping it but I just assumed it was cold.
The day’s destination was Alston covering several trails I’ve not been on before and some I’ve only done in deep snow. There was an interesting ford with steep hillside with switchbacks either side and a steep rocky climb I quite enjoyed but one of the guys came off on it (nothing serious). We passed through showers but there were also dry times too which wasn’t too bad.
Just before lunch, the bike died suddenly with what looked like loss of electrics. It wouldn’t kick back to life but did when I switched the fuel tap from main to reserve. It seemed fine so I continued on making a mental note to pull the tap apart and check what it was doing at some future date.
We went up to Hartside cafe for a change instead of the cafe in Alston and it was filled with cyclists who looked rather weather beaten. After lunch the bike needed choke to start and took a bit of getting going yet again.
We took a trail I quite enjoyed above a stream raging with white water, crossing through overflowing streams in a few places. We also passed a group of about 20 people (not walkers but people on some kind of tour?) who looked totally bemused that a set of bikes could travel over the ground they could barely stand up on :). Getting back to the road from that trail saw me nearly getting stuck in a bog – I was trying to catch the group up, took a different line to everyone else and the bike nearly came to a stop and was sinking in a boggy bit. Leaping off the seat to the side, keeping the throttle open and pushing got it out thankfully though.
The next ford caused me some fun. There were two lines out, one nice looking and one with a steep rise up a large rock. Half way through the ford the bike went offline and I ended up going the rock route unexpectedly. If I’d applied enough power I’d have made it but I didn’t and the front wheel got up but I then stalled. This then meant reversing the bike back into the river and restarting it with the result of properly wet feet. It was kind of inevitable I guess. Nick then dropped his bike a couple of metres further up the slope to make me feel slightly better.
We were slowly winding around back to Hexham near Slaley when the bike totally died again with something suspiciously electrical looking. To rule it out I checked there was fuel to the carb. I also drained some fuel from the carb in case it was water related but it wasn’t. Messing around with various plugs suggested no spark. To conclusively prove this I ended up putting a finger into the plug cap and since I didn’t fly across the moorland when someone kicked the bike over, it was safe to say the electrics were dead. We tried bumping it and it did start but then nearly died, started and then died again.
A check of various connections didn’t show anything obvious so we decided to tow it remaining few miles back to camp although some members of the group were sceptical you could do this. I’ve never been towed on a bike before so this was an interesting learning experience. We did however make it off the trail back to tarmac and then back to the campsite with only one really hairy moment. At least this happened near the end of the day on the way back and near the site I guess. I was also very grateful for the tow back! 🙂
Back at camp I took it further to bits but didn’t find anything obvious despite a couple of false leads. It did however start and I did a couple of loops around the field however it was miss firing and not reving – I could hold it at full throttle with not much happening.
At this point I was offered lots of semi conflicting advice. The most convincing argument was stator coil failure, intermittent or otherwise. I was also told there were separate windings for the ignition coil power and the lights and that the pickup coils could have failed too.
I’ve since had the manual out and traced bits of the loom and can say for sure it only has one set of stator coils driving everything and these run through what I suspect is a rectifier only (not a reg/rect combo). It has 5 leads, 3 from the stator coils and the other two are +12V and ground. The +12V goes across a large condenser which is why I suspect its a rectifier only.
The stator wires have the same resistance between each pair of wires which suggests if a stator coil has failed its only under load/temperature. I stuck a diode tester on the rectifier leads and saw 0.7v drop between ground and two of the phases and between those two phases and the +12V consistent with a half wave rectifier setup. The third phase doesn’t give me a voltage drop reading. This suggests a couple of the diodes have failed or I’m wrong about it being a half wave rectifier or I’m just plain wrong :).
Its also possible something like a magnetic pickup has failed but if that were the case it wouldn’t explain the total loss of electrical power I’d swear I saw as it was dieing. Its also been a hard to start since I’ve owned it which could possibly be consistent with it being a single diode down? Loss of the second diode (or maybe more at higher temperatures) has then finished things off?
Anyhow, regardless, there was no way I could use the bike today (Sunday). I stayed there last night for more bevvies, fires and horror movies on the big screen which was good fun. It was sad to see everyone riding off for more fun this morning and not being able to join them but there will be other opportunities. Thanks go to the local TRF group for a good time!