Thursday night was a bit of a rush, it being the first dry evening since the kart got soaked on Monday – I had dried the kart as best I could (given the constraints of working on a kart sat on a camping trailer inside a single garage) but there was still a fair amount of moisture around the engine mount so I chose to remove it and make sure everything was clean and dry. Not the best time for a first solo removal of the engine and exhaust perhaps but it needed doing. I also had to reset the front width after widening it at Llandow and I got as much ready for the day as possible: changed the sprocket, mixed some new fuel and slightly overinflated the tyres so that I could tweak them in the morning.
We got to Clay Pigeon Raceway about 20 mins before the track opened, signed in and were told to have a few runs and the ARKS examiner would come and get us when the time was right. I had been a bit worried on the drive down about the possibility of a repeat of the starting difficulty we had last time so I was relieved when it started first time. I ran my normal wheel, hub and chassis bolt checks and, unusually, we were out for the first session 🙂 We had a stuttering start though – Junior came in eight laps reporting the back end felt loose. I wondered if this was a tyre pressure issue so I dropped them down a notch. Second time out he complained it felt even worse! With his hesitancy from Llandow in mind, I assured him that nothing was loose so there was no safety issue and sent him back out to give the tyres a good warm up and see if the handling improved. I widened the back end by 5mm on each side when he came back and, from then on, he was happy with the handling and was soon pushing it. It was only during the fourth session that I realised the ARKS instructor was marshalling so that he could watch Junior, who by this time had beaten his previously best lap time from our February session. The instructor was more than happy with his speed and it was at that point I stupidly commented on it being nice to have the kart running without issue. No more than two minutes later, the kart is parked up on the exit of Billies and Junior is inspecting the back end. I made for the trolley park.
This was an interesting one: not only had the chain had come off but the sprocket was hanging on by a single bolt and one part of the sprocket protector was sitting on the axle, next to the chain. I had lost two of the three bolts from the sprocket carrier although one was bent and wedged in the back of composite chainguard. There were no nuts, including those that separated the sprocket from the sprocket protector (on which the fixing holes were now very worn to the point of being largely useless). I had lost parts on track yet again… 🙁 This was and still is something that I am desperate to see the end of – this particular problem was a new occurence and I can only assume that the nuts on the outside of the plastic sprocket protector had come loose. Just like the exhaust screws, it seems that once one goes it’s only a matter of time and the sprocket nuts were not nylocs, nor was I checking them between sessions. I removed all the relevant parts – there was composite chainguard ‘dust’ all over the engine, chain and chassis. The chainguard itself was cut up and the sprocket had worn on side of the teeth. I disposed of the sprocket, patched up the back of the chainguard with tank tape, bought six new sprocket carrier bolts (we – and every other kart I have ever looked at – had only three bolts in place before now) and cleaned everything up. We missed two sessions but at least it gave us some time to have some lunch.
As we were ready to head out again, Junior was called for his ARKS driving results and theory test – the only comment was that he needed to use the kerbs in the Esses and he got all his questions right in the test, meaning he passed his test 🙂
We made the most of the remaining four sessions, running until we were kicked off at 5pm. Junior had some fun racing with a couple of his friends he knew from Teamsport Bristol – one a Senior Max, the other in a Mini Max which made for a surprisingly entertaining spectacle and he was chuffed to post a new fastest lap of 36.92s, especially as his tyres were probably making a farewell appearance (they were used when we got the kart and he’s since done over 400 laps on them!). All in all, a good day – ARKS test passed, 157 laps ‘bum-in-seat’ time and a new fastest lap, only tainted by the sprocket bolt problem although I am now running six bolts (three of the holes on the sprocket and sprocket protectors are now badly worn) and checking them after each session (they do need tightening up every time, even with nylocs – I wonder if it is the plastic sprocket protector that doesn’t really allow for a firm tightening of the nuts).
Cost of day: £12 petrol, £7 petrol for 5l super unleaded for the kart, £85 ARKS test fee (including track practice), £1.50 for 6 sprocket carrier bolts
Total spent so far: £2,680