Category Archives: Running a kart

Practice 11: best laps and breakages

Posted on by
Reply

The second of back-to-back Saturdays. Once again I found myself awake in the early hours, brain totally engaged thinking about the day. Having found the benefits of an early arrival (i.e. plenty of time to get ready for the first session without rushing) to my liking last week, we arrived an hour before the track opened. Unlike last week however, I hadn’t really been able to do as much of the preparation at home the night before owing to the poor weather (the garage has insufficient space to actually work in it and the lighting is awful) so the tyres (a fairly decent ‘new’ used set bought from the forums some time ago) hadn’t been inflated, I hadn’t gotten the new carb gaskets fitted, nor check everything over properly after I had stripped the back end down to dry it last week. The preparation hour was a bit of a rush; I put the new 3l fuel tank on, corrected the kind of mistakes you make when working in the dark (i.e. a front wheel with three wheel nuts but only two bolts used!) and got everything set. We were on the grid when the cadets came off at 10:10.

Our first problem of the day: the kart wouldn’t fire. I gave it a couple of aborted push start attempts but there wasn’t even the hint of it starting. I took it back to the pits and checked the ignition box wire connectors were ok and then checked the spark plug and found that we were not getting a spark. I whipped out the new plug that I had bought in the week for just this purpose and things looked more promising. Hastily, I tossed the old plug in the bin and we went for another attempt at getting on track. Once again the kart is showing no signs of starting so back to the pits again – it seemed the sparking was intermittent. I had used my only spare HT lead at a recent practice at Dunks. Good job that Clay has a shop… only the shop didn’t have one! Fortunately, I was able to borrow one (from my good friend also known as KartingDad’s Karting Dad!), swap the lead over and get the kart starting reliably on the stand and running fine (shame about the plug I threw in the bin full of wasps but never mind).

Junior was on the grid for the start of the second session but only managed three laps before coming in to complain about his brakes. I could see that one pad was rubbing the disc engine-side and there was quite a gap brake-side but assumed, as he had been running ok, that it I could just adjust it at the end of the session. He did another 15 laps but with a slow best time of 39.3s and still complaining about the brake. Back in the pits, I was surprised to see the brake-side pad was rubbing the disc and the gap was now engine-side. If you are thinking “grub screws”, you would be correct: the grub screws had abandoned ship! Pleasingly, I figured that one out straight away too. Disappointingly, this was a mechanic error – I wasn’t overly tightening the grub screws knowing grub screw damage can severely weaken an axle. I have to admit that I hadn’t checked the grub screws at the start of the day so it could well have been that I hadn’t tightened them enough (even for my liking) after refitting the axle. Everything else was still aligned and looking good so it was just the grub screws required – you’d think these would be in stock wouldn’t you? As far as shop stock went, today wasn’t my lucky day so they gave me the only one they had. Having lost a couple at home recently, I only had one spare and my Karting Dad had one also. Cue wandering around the pits trying to buy spares! I managed to get some but it wrote off the remainder of the morning with only 18 laps under our belt and a best (and faulty brake affected) time of 39.1s.

The third session was more like it: 23 laps with a best of 36.6 and lots of time still evident in Junior’s lines. The fourth was better again: running with the camera on-board for first time of the day, Junior managed a 36.5s before the camera mount snapped :S See if you can spot the moment in my YouTube video. I am not convinced this punt on the camera is working – the camera itself is fine but the case and mounts haven’t looked up to the massive vibration that karting poses. For this session we were also running with the MyTach GPS watch. I’ve still not really read up on this but the watch gives you top speed readings and we were looking to test sprocket sizes. Running a 78 sprocket (what we had always run at Clay although I know the quicker guys run a fair bit smaller), we did a fastest lap of 36.57 with a top speed of 64.6mph (ironically analysis at home showed this was not on the fastest lap, which included a top speed of 60.8mph). With our problems seemingly behind us, we switched to a 76 sprocket and ran the GPS again. This time Junior put in a 36.42, the top speed on that lap was 63.8mph and his maximum speed during the session was 64.7mph. Not much in it, I am sure you will agree – I put this down to inconsistency, particularly out of the Top Bend but there was some interesting data in there: he was 3mph quicker down the straight into The Hairpin on the smaller sprocket.

The track then seemed to cool a little and I think my not increasing the tyre pressures a fraction may have cost us a few tenths as we drifted in the 36.6/36.7s laps before we encountered our biggest problem of the day: Junior had been holding up a couple of RotaxMax’s for a few laps and ran wide at The Horseshoe, matey decided to stick his nose up on the outside and, as Junior moved wider to get a line for the bend, they hit – flicking our back end up and causing Junior to run onto the grass. He rejoined the track and ran for another 8 laps. I was very surprised when he came in and I took the chainguard off – the chain looked blackened and dry (it had been freshly lubed) and was missing a few chunks, then I noticed the teeth on the rear sprocket (a brand, spanking new one that day) were wrecked which lead me to a front sprocket with some nice sharp spurs! At this point I needed KartingDad’s Karting Dad (again) as I had no idea how to remove a front sprocket and have learnt I need to buy some new tools :S With hindsight, either of two changes I made during the day may have contributed to this: I removed the sprocket protectors after deciding to use 6 sprocket bolts instead of three (it looked like the front sprocket alignment was a little uneven as the rear sprocket was rotated so I add the extra bolts in case this was the cause and the protectors have three warped holes that no longer easily facilitate the extra bolts) and the chain was running a little looser than I normally have it (on advice!). We went back to the 78 sprocket (now my smallest), a 110  chain (also now my smallest) and fitted a spare front sprocket (thanks again, spares :)).

The track was quieter now and Junior spent the last couple of sessions racing his friends. His lines through the afternoon had really come on – a screech and a lift entering Billies always looks good, taking The Esses with a decent amount of kerb was becoming more of the norm and, although his exit from The Hairpin was still a little tight and he had acquired a new, slower line through The Horseshoe, he was carrying [a little] more speed into and out of the Top Bend. New PB!!! 36.11 🙂 Racing was obviously paying off. For the final session of the day, he spent a few laps following the South West Junior TKM champion 😉 until said champion decided he had enough and wanted to put Junior in his place. Junior didn’t mind though, he was chuffed to bits with another new PB – 36.06s.

So we got off to the worst possible start, endured a pretty expensive day, breakage wise but ended up clocking 166 laps and Junior making further progress.He is definitely quick enough to race. I have no lofty goals/dreams about exactly how competitive he will be, it would be nice to be close enough to the pack to race someone but I doubt that will be the case initially. Whether I am ready to race is another question. I am still making mistakes but I think that is just human nature – I’ll make more than most mechanics, I just need to make sure I learn from them! The troubleshooting is a worry as, if things go wrong, there is no second engine to pull out the trailer, nor is there likely to be for some time. We’re just going to have to see how we get on 🙂

Cost of day: £12 petrol, £7 fuel for the kart, £35 practice fee, £5 grub screws

Cost of replacement stuff: £10 ‘new’ chainguard from eBay, £100 new spark plug cap/spark plug/HT lead/6 grub screws/10-tooth front sprocket/Talon size 76 rear sprocket/Panther (I know I could have spent less but I am keen to see if it is stronger and longer lasting) 108 link chain (from Kart Parts UK/Spellfame)

Total spent so far: £3,396

I plan to limit outgoings to race weekends and associated running costs/repairs only for the remainder of the year so kick me if you see me post about new bits and pieces!

Changing tyres ain’t easy!

Posted on by
Reply

This week I bought a bead breaker, a tyre removal tool and some tyre paste as I wanted to get some fresher rubber on for this weekend and I cannot keep asking another Dad to host me whilst I use all his stuff to change tyres. There are two parts that I really struggle with: getting the tyre removal tool disc into rim (so that you can run the tool around the tyre prior to removal) and then working the tyre onto the rim. I think it’s just my general patheticness as an office boy: getting the removal tool in place is about brute force and working the tyre onto the rim seems to be all about finger strength – and I don’t really have any! Changing the wets last time wasn’t too bad but the new(er) slicks I just put on were some else entirely. Once again I can only claim credit for half the set but I’ll be on my own next time so more practice is inevitable.

Cost of tools: £25 bead breaker and removal tool, £3 tyre paste

Total spent so far: £3,227

MSA karting license arrives

Posted on by
Reply

Junior’s race license arrived last week. The application form had been ready since he passed his ARKS test in May but there seemed to be no rush. We didn’t have a lot of choice given all of the tracks in the area are MSA affiliated but that was fine with me; I think I’d prefer to run under the UK motorsport governing body. Then you start to look at the costs…

  • MSA ‘Go Karting’ Stater Pack: the all-important DVD containing everything you need to know to pass your ARKS test, an application form unobtainable elsewhere, the rule books (which you get another copy of when you receive your license) and a Demon Tweeks catalogue! £50
  • ARKS test: £93
  • Junior license application: free
  • Parent license: £17

I don’t begrudge paying for the service but, on reflection, there is a lot of bloated cost in there. To attract new people into karting the entry costs need to be lower, I think you could charge £20 for this and still make a healthy profit. The ARKS test is what it is and at least at Clay this cost includes a day’s practice. It is nice that the junior license application is free but the Lord giveth and the Lord taketh, as they say… I am fundamentally against the parent license concept; I understand it was introduced so that juniors did not get penalised for their parent’s misdemeanors but what better deterrent than to exclude juniors if their parents cannot control themselves? For Dad/lad combos, excluding the Dad is the same thing anyway – Junior’s Mum isn’t bringing him karting! It would be fair to say that I definitely begrudged paying for a license to take Junior karting.

Consider this more of a grumble than a rant 🙂 Here’s hoping we are making the most of the license very soon!

Practice 9: Hmmm…..

Posted on by
4

A fair amount had changed on the kart since our problems at Dunkeswell; the back end had had some attention as I had fitted and subsequently returned a used axle, I had also fitted the OTK foot rest in the expectation that it would give Junior something to press his heels into when braking and I had ‘expertly’ created a foam insert for the seat after Junior had complained that he was uncomfortable in the seat in longer sessions. I had some things to test too: I had tightened the nassau in a bid to improve upon the vibration suffered by the ActionPro and I had also been lent a MyTach GPS watch to test (thanks, Colin!).

Again, we left late – only 15 mins but it meant that we didn’t make the first session although only because went on the track before it opened in order to set the GPS position and decided to walk the track since we were out there. Our first lap lasted all of about 30 seconds as Junior complained that his brakes weren’t working. What he actually meant was he didn’t like the heel rests and they restricted his use of the brake! Our second session ended with the kart stopping on track; I had hand-tightened the spark plug having noticed it wasn’t seated as we were pushing the kart to the pit lane and so we had lost compression (Noob Lesson 1 for the day).

We then had some decent track time mixed with some more mistakes on my part: a loose floor tray, lost nassau bracket bolts, another [different] loose nassau bolt. These are things I have to admit I’d never checked mid-session but, as Junior was starting to [sporadically] hit the kerbs through The Esses, the kart was starting to get a little roughed up (Noob Lesson 2 – check bodywork through the day). The seat insert of which I was very proud was a flop – the sides had to be removed in order for Junior to fit in, then he decided he preferred the seating position without it! We never captured any data on the MyTach, either through user error (not hitting the ‘Start’ button) or taking it off whilst we found some reliability and forgetting to put it back on again! The ActionPro still suffered vibration although tightening the nassau did help a little.

The biggest disappointment was the times we were producing – 37.x throughout the day, a second off of our best at our last visit in June. Conditions were pretty similar; the weather was warm and although the kart setup was not identical (the rear axle was at it’s middle height whereas it was low last time, we may have had a different carb and the tyres had obviously seen a little action at Dunks in July) but I didn’t feel that explained such a loss of pace. You could see that it was taking longer for the regulars to catch Junior on our last visit but that wasn’t the case this time. Junior was working on his lines but there is still a lot of room for improvement, most significantly in his lines and his braking points. Don’t get me wrong I very rarely criticise him; it would be a bit hypocritical as I am still making noob mistakes! He wants to race and we’ll do that when he is ready. I came hoping to confirm our readiness and left knowing that we still weren’t there yet. When we bought the kart I said we’d look to get a few races in at the end of the year. I thought we were a little ahead of plan but maybe that isn’t the case.

On the positive side, Junior ran for 170 laps despite the mishaps, did improve his line through The Esses a little and nothing unexplainable happened to the kart. Remember there is no such thing as bad seat time… 🙂

Cost of day: £12 petrol, £7 fuel for the kart (still plenty left from last time), £35 practice fee

6 nassau bracket bolts: £3!!!

Total spent so far: £3,143

 

The kart… it works (I think)

Posted on by
2

I had been meaning to investigate the cause of the problem that caused an early end to our day at Dunkeswell the following day. I needed Junior to be home to help me get the kart off the trailer lid and onto the trolley (the wife refuses after hurting her back the only other time she tried – I won’t take that one any further!) and I had the kart all ready for his teatime arrival so that I could replace the fuel tank and try starting the kart. It was pretty dark when he got home at 9:30pm!!! Barely light enough to get everything replaced/checked never mind starting at 2-stroke go-kart in the front garden at such an unsociable hour. It had to be done though although a couple of quick starting attempts proved fruitless and I quickly threw in the towel.

Ten days passed (is it just me or is the kart easy to ignore when you know you have a problem to resolve?) and I mustered just enough enthusiasm to try again. The carb was holding the fuel ok but the kart just wasn’t firing up. I rested the plug on top of the engine and tried starting again to gauge the health (or otherwise) of the spark – there was no spark! I replaced the spark plug with a couple of the spares although one of the few pitfalls in buying a retirement package is that you’ve no idea as to the quality of the spares. Could three spark plugs all be bad? I made a note to myself to buy a new plug just to keep for troubleshooting and wondered what I could next. I’m still not great at engine problems but the only things I could test were the PVL coil and the ignition HT lead – both of which I had 🙂 The HT lead was the quicker win so that got replaced first. I was very pleasantly surprised to see a spark and then subsequently hear the engine fire up. I couldn’t run it for very long but it started a couple of times. The HT lead did suffer some damage when Junior had a Rotax drive over him but it had been fine until now. Ho hum…

Our race plans have been set back though – we need another good practice day now so it’s looking likely that we’ll head to Clay this week and hope for the best.

And then there are the times when you just want to scream

Posted on by
Reply

Having prepared the kart earlier in the week, I wasn’t really planning to spend much more time on it before we take it to the track on Saturday. I needed to drill a small hole in the nassau that could be used to secure the ActionPro but the rest of it was done but with the hot weather almost guaranteeing grip I decided to lower the chassis. This is a bit of a pain as my sprocket carrier *really* likes my axle – you could say they are pretty much inseparable based on the only time I have removed the axle. I wasn’t looking forward to this and rightly so as it turned out – it took over an hour of hammer ‘tapping’, rotating and lubricating to get the sprocket carrier off (it wasn’t helping that the sprocket guard was cushioning my efforts). It was getting dark when I was putting the back end back together and it was only when the wheels were back on and I went to fit the chainguard that I realised that I had not fitted the chainguard mount brackets…

So tonight, when I should just have been nipping out to get some super unleaded, part-loading the car, relaxing before having an early night I’ll be irritating the neighbours with an hour of constant banging whilst cursing silently and continuously.

This highs and lows, eh?

Practice 7: Engine run-in and new fastest lap (not at the same time, of course…)

Posted on by
Reply

Today was our eagerly awaited practice day at Clay: having weighted the kart at Junior’s race weight and added the black restrictor (which is actually silver but, hey – it was a 99p eBay purchase and I took a punt, then subsequently discovered it wasn’t MSA legal having lost it’s anodised colouring!), I was really keen to see how Junior managed having picked up some good pace when unweighted last time. I awoke early as I seem to on every kart day – 4:55am this time, brain fully switched on running over the things I needed to remember to take and then all of the things to remember when we got to the track. Up at 6:10, out the door by 7:45 (just in case we hit Glastonbury traffic) and at the track at 9:15 – in plenty of time to get things sorted 🙂

Before we could really get going, our first business was to run-in the engine. This was our first session as a licensed driver 🙂 but Junior was driving up to 8,000rpm (or dangerously slow as it seemed) and there were a couple of close calls in our ten minutes on track. Afterwards one of the stewards suggested we continue running-in the engine with the cadets, which I was more than happy to do. This worked in the second session,when he moved up to 11,000rpm (and I bravely ignored a broken toe to resume bump starting duties ;)), but not in the third session where we were getting up to 15,000rpm and he got told off for racing cadets (and breaking my 40s lap rule!). Our job was done at that point though and, although he was still on a ‘not above 15k’ brief when back out with the adults, we could focus on the more intriguing part of the day.

It didn’t start too well – for the first time in our ownership the kart didn’t start and I was shattered, having ran myself into the ground well past The Kink! I am not sure Junior fully knows what he needs to when we are starting although, if I am honest, I probably didn’t fully understand either. It had just worked nicely previously. With some tips from friendly Dads (don’t pump the pedal, wait for the engine to spark then slowly and gradually accelerate), we got out again for three laps before the end of the session but, most importantly, it started fine.

After that things went just about as well as we could have hoped – the kart ran, we had no mechanical problems *at all* 🙂 (although Junior did spin into the tyres exiting the Top Bend), he was happy with the kart and preferred the handling with the extra weight on board (the back end seemed much less inclined to hop out as he accelerated out of the corner) and he knocked 0.7s off his previous best and recorded a 36.21. He was a little disappointed not to break the 36.0s mark although my biggest concern was the kart’s weight – Junior stood no chance of lifting the kart off the floor and I was reliant upon friendly faces to help me get the kart back onto the trolley. I don’t really want to keep putting on others so I might need to look at the self-loading trolley options. Chances are though, he’ll start growing by the time I finally get something sorted! All-in-all, it was a really good day; I think Junior is quick enough to race now (without being lapped!) although we have a lot on next month and I have promised him we’ll go to Dunkeswell for a practice day. August’s race meeting at Clay is the target 🙂

Cost of day: £12 petrol, £10 petrol for 7l super unleaded for the kart (session was free as we had a credit note after our accident).

Purchases since my last post: used set of slicks from the forums: £30

Total spent so far: £2,977

Farewell first set of nearly-new slicks!

Posted on by
Reply

They have been on the kart since we bought it and subsequently done 408 laps (or 241 miles!) but the time has come to bid farewell to our first set of nearly new slicks. Ironically Junior set his PB around Clay in his final session using them but there is no time for sentiment 😉 I have replaced them with another set of nearly new slicks that I bought for £30 from one of the forums 🙂 Removing the tyres from their rims was a smoother process than putting the new ones on – especially the rears. I think I could claim credit for maybe 1.75 of the 4 tyres so definitely more practice required. Not sure my office fingers are up to the job!

Whilst I was doing ‘kart stuff’, I completed the addition of the weight to the seat so we are almost good to go on Saturday (I have some good friends offering to help me with the push starting if the toe is problematic). I am really looking forward to seeing how Junior fares in the kart at his racing weight. Not so much looking forward to lifting the kart onto the trolley with him – he really struggled before we added 7kg…

Warning: motorsports can be dangerous!

Posted on by
Reply

Sorry for not having posted recently – as you’ll soon see things have ‘interesting’ of late :S I’d been spending quite a bit of time on the kart: I needed to put the engine back on following it’s rebuild and, whilst the engine was off, I had wanted to give the back end a good clean but had trouble removing the sprocket carrier so I was keen to put that right.

I spent three successive evenings working on the kart last week (when it comes to kart maintenance one thing invariably leads to another), firstly tackling the sprocket carrier: it was a little awkward as the sprocket protector was still in place on the brake side of the carrier but tap by tap, I managed to knock it with a hammer (lubing, hitting each arm of the sprocket carrier in turn and repeating until free – all whilst I had a pair of screwdrivers carefully tapped into the slots on the carrier to help free it from the axle. I got there in the end!

Whilst cleaning the back end, I noticed that the chassis was running at it’s lowest setting:

Tonykart chassis height

This is how you would set up a kart in hot weather, where you had too much rear end grip (you would typically raise the axle in the wet when you want to raise the centre of gravity) but this was not how I wanted the kart set up whilst Junior is still learning to drive so I removed the axle and set it to the standard (middle) height. And of course, I took the opportunity to clean the chassis around the bearings whilst I had the chance 😉

I then decided to adjust the seat as my measurements were some way from the Tonykart recommendations. With hindsight this might not have been a great idea: it took a long time, Junior got hacked off holding the seat in place and I don’t think I ended up much more ‘optimal’ than I had started out. And I forgot about the weights when putting the seat back on.

Ah, the weights… the highlight(?) of last week!!! Having weighed Junior at Llandow I reckoned we needed 7kg of lead and the black restrictor to put us at the correct race weight. I already had 3kg that came with the kart and I bought a 4kg lump for £15 from the forums, it just needed fitting – 3kg went on the side of the seat (low on the brake side to offset the engine weight). After hammering the lead weights flat so as to fit flush to the seat, it was pretty straightforward. The 4kg weight had other ideas – I hit it flat and held it in position to mark the drill holes. My marking pencil had disappeared so I went off to fetch it, holding the lead in place against the seat in one hand. As I went back outside the lead slipped and I instinctively (and stupidly) put my foot out to break the fall!!!!!!!! Painful was an understatement.

I got back from hospital just before 2am with very swollen, very sorry looking broken toe. Funnily enough, I haven’t done anything on the kart since! I have a injured toe photo that I took in A&E that was very popular with my Facebook friends but I’ve decided not to post it here 😉 I am hoping to be fit enough to run Junior at Clay on Saturday but push starting is an obvious concern. Fingers crossed…

Cost of an especially damaging 4kg lead weight: £15

Total spent so far: £2,925

Engine rebuild

Posted on by
Reply

I’d been considering getting the engine rebuilt for some time; I bought the engine with ~3 hours on it prior to our test/purchase day (onto which I added a couple of hours just in case) and we had put 6 hours on it following the ARKS test. Given the recommended rebuild time of 8-10 hours I thought it best to err on the side of caution and book a rebuild.

The big question was who to use? The previous owner had had both his race and this practice engine (I bought the latter) rebuilt by Dave Litchfield – one of the best know engine builders in the country but I didn’t think I was really in a position to justify the additional cost of posting the engine for it to be rebuilt by the man lots of race teams use (not to mention I think I might have been a little out of my depth in any service discussion!). Looking at the numerous local options, I had heard good things about all three of the builders I was considering. I assumed that the quality of rebuild would be pretty much the same given the limited amount that can be done with a TKM engine so in the end it came down to convenience: I’d just finished a day at Clay and it was easy for me to leave it with Lee Rennison, the ARKS examiner at Clay (no conflict of interest here I hasten to add – I didn’t mention the rebuild until *after* the test!). He offers a rebuild service and I figured it would a) save me cleaning the engine when I got home, b) save me having to take or send it anywhere and c) potentially offer some local support if I ran into any engine issues at the track. And he’s a really nice bloke too!

The rebuild took a week and I picked it up today. The engine was in really good shape so I could probably have gotten another couple of hours in. Had I not lost the receipt at the track I could have told you exactly what I had done but it included new top and bottom-end kits, gaskets, bearings, a piston and three carb rebuilds for a [relatively] palatable £230. I am sure Junior will enjoy running it in later this month!

Whilst we were there I attempted to make Junior watch the drivers practising ahead of tomorrow’s race fixture and make some mental notes of the race lines. He never seems to listen to me, nor anybody else for that matter but I really hope watching a constant stream of drivers taking a decent chunk of kerb through The Esses might sink in. We’ll see…

Cost of engine rebuild: £230

Total spent so far: £2,910 (starting to regret keeping a running total now…)