AdamR28

Some race teams will bin tyres after one session, since that's when they've given the best lap times. Others will run them down to the wear markers. The first ones are ok, the second ones are only fit for skidding about on or the bin... They also degrade with UV light, so old tyres sat around for a while are crap too. As Alex eluded to, if you have a reliable source then buying used tyres is fine, but I guess there's always someone out there trying to flog naff stuff

Yeah, especially if there wasn't a lot of rubber left on them. Had this issue on a track day recently, below a certain amount of tread depth the tyres wouldn't hold any heat and it was suuuuper slippery.

And I was trying to be civil. Oh well

I'm not sure actually. A lot of trials is really psychological it seems. One rider does something which may well be placebo and everyone copies, it's just the way it is. No offence at all - people can do what they want, but the physics doesn't change.

Seems weird. Nothing else changed on the car other than a fresh set of tyres?

Just needs some tags for the embed Edit... or not. What the hell, haha. Oh well, here it is anyway. Enjoyed that, nice one! Sorry Tarty Days made you buy a 24" haha

One 360 degree crank rotation still gives 18/15ths of a rotation of the rear wheel though, so the bike travels the same distance... Your foot travels less, yes, but you can't start closer to the obstacle because the bike travels the same amount of horizontal distance. By your foot travelling less distance it also confirms that shorter cranks give less leverage: work done = force * distance, so if you apply the same force over less distance you have done less work and therefore the bike hasn't accelerated as much.

Thanks Lukas! You seemed to capture almost everything I know it's a lot of work to put together a long video like that, so, thank you!

I know there are normal and healthy 172 engines but that looks a little optimistic haha Still, the shapes of the curves show all is good. Be interesting to see the gains if you can get a couple of runs on the same dyno after its fitted!

Very tricky question. Yes, it's sort of a piece of history, but it's not really old enough to be worth anything much other than to a very small handful of people. In this case it's worth what they are prepared to pay for it, pretty much. If you ignore the logo and oldskool ness, a full bike of old parts that doesn't ride very well might be worth £3-400?

It's normal, it's meant to be hard to go back on, or else it will also come back off easily

I getcha - should work fine I reckon. On my MX-5 (for example), 14 degrees is about 20-25mm worth of length (if that makes sense) at the crank pulley (so about 70mm radius)... It'll run fine at anything from around 8-16 degrees BTDC, so if you're using the flywheel which is a much larger diameter I reckon you can get that pretty accurate! Some sort of scribe might do the job too, you only have to get rid of the muck on the pulley and it'll give a pretty clear marker with the strobe

Good stuff Glad to hear it! A line of Tippex will be fine for timing it up I reckon (that's what I use anyway).

I tried to get the video to start at 6 seconds, but no joy. You get the idea...

This video wins! Thanks for letting us premiere it at Tarty Days

Ah, poo - sorry - I think you'd already said that? :$ Dipstick in No1 is a good failsafe in that case! Told you that you had the skills to work on something like this Diagnosing issues like your flywheel using logic is half the battle! Had something very very similar with my car recently - with the fuelling being screwed the plugs were fouled. New set of plugs and it runs spot on again. Worth a shot for ~£15? Or at least take them out, plug one back into the lead and ground it on the block, then turn the car over on the starter and look for a good spark. Repeat with all 4. You should be able to see the spark even in daylight - if it's dim or non existent then new plugs should do the trick. From the links it appears the camshaft marker is viewed from the 'back' rather than the front? (Sorry if that sounds stupid but it's how I understood it...) It will usually be an indent or notch in the cam sprocket, rather than any sort of coloured dot / line. Also looks from the diagrams that it should be timed with that notch facing vertically upwards, even if the 'pin' n the block is missing that should get you somewhere near?

Ah-ha, apparently the timing mark (for the crank) on that engine is on the flywheel rather than the sprocket?! If this looks right? (Maybe a bit late but would explain why it was a bit tricky to find TDC) http://i.fixya.net/fixya20/uploads/Images/tdisline_14.JPG A few other bits I found... Hopefully be helpful for timing up the top end? Sorry, not had chance to read through fully... http://retrorides.proboards.com/thread/47397 http://members.tripod.com/darrin_smith/porsche/924cam.html Any use?

Not sure - but the timing mark on the sprocket should line up with another timing mark on the block / cover when the crank is at TDC. Which car / engine is it exactly? (Sorry, I can't remember...)

See, I've done some fairly involved stuff to engines but never a gearbox, I'd be too scared! Haha. You'll be absolutely fine

Engines are no more difficult than any other part of the car, especially lovely old mechanical engines just the consequences can be more dire if it goes wrong, haha. Confidence!

The dipstick down no1 cylinder is good enough usually And yes, 3 teeth out is a lot! One tooth is enough to make it run a bit shit. You've got the skills to do it, start from scratch and double check everything as you go, you'd get it bob on in no time.

Awesome riding.

Music swap fail I'll try and have a look later...

There is no 'right' really, it's a personal thing - 175s for me.