Motorcycle and Scooter appreciation

It's almost never pure lean that makes you lose the front, it's brakes, bumps or transitions on/off the throttle. You can go knee down basically straight away on most good street / track tyres but you need to be very careful carrying the front brake. By the third lap, everything should be up to temp for sure.

What sort of tyre pressures were you running?

I’ve been trying to reach the sidewalls on the skinny tyres of the little 125. After >30 minutes of riding, the rear is warm to the touch but the front is barely off cool.

Thanks to constantly caking them in dirt I also get a fair idea how much lean I’m getting once back on the road. The front patch is barely 2/3 compared to the rear.

I suppose these two things are thanks to the front tyre being in the wind, and the weight and lean all happening at the back.

Scaled up to a real bike, maybe your front just wasn’t warm.

I'm not skilled enough to try trail braking so can confidently say I wasn't on the brakes, changing down alone often felt like enough engine braking. I was running what Pirelli apparently recommend for the Diablo Rosso II on track...31 psi front and 26 psi rear.

@pdlouche from looking at the sidewall this is what it suggests to me. I've been dragging knees after just 2 laps when riding that track in the past so seems weird.

So much up front? Maybe too hard and washed out?

Takes a bit more stick to distort the sidewall of the front and scrub it to the edge. Were you just beginning to crack open the throttle? Sometimes the weight transfer is enough to wash out a cold front if you're well leant over.

Definitely a conundrum mate, don't worry about it. I've been on my arse many times going 'how did that happen?' :)

The last trackday I did at Rockingham I lobbed it on about the third lap and really couldn't figure out how. After, I found a photographer had pics and despite thinking I was off the brakes, I was still carrying a fistful. Silly me. It's really good practice on track to take your fingers completely off the lever when you're done. Found the just before pic here!

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Takes a bit more stick to distort the sidewall of the front and scrub it to the edge

That would explain why it hadn't blistered on the front right. I was entering the corner with more entry speed than before but just put that down to gradually building up pace.

Agreed these things happen and glad I'm not the only one, just don't want to scratch my bike if I can help it! Might even look into doing a race school or just renting a track bike to improve my skillz.

Never got a chance to go :(

https://www.visordown.com/news/general/honda-ron-haslam-race-school-will-soon-be-closing

you need to be very careful carrying the front brake

Yeah I'd never do that

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ha! Anyone have a recommendation for a summer jacket? Nearly died of dehydration last weekend...

I’ve got one of these.

Served me well all the way across America in a heat wave including 45 degrees between Vegas and LA and being stranded in the middle of New Mexico for a hot Sunday afternoon.

I have this, not sure why I didn’t get the silver version tbh but it’s pretty great even on a full fairing bike.
https://www.sportsbikeshop.co.uk/motorcycle_parts/content_prod/317150

Website offering a towelled 375g/sqm aramid fabric wanted £25/sqm plus vat, sod that for messing about with.

Took a slightly expensive punt on a roll of ex-MOD contract para-aramid from ebay. From the photos looked very thin. Seems to be around 115g/sqm, which is around 1/3 to 1/4 the weight of the aramid/kevlar I saw elsewhere. It also works out at something super low per meter too, so well worth testing and potentially making some layers to wear inside the textile kit if I was so inclined.

Testing was very unscientific.

Fire on the hob after one minute it turned to tissue but never actually burst into flames. So, fire retardancy good.

My sharp scissors cut through it with a bit of concentration. So not great as a single layer for anti-stabby but great considering I’ll have to make a pattern to sew. Multiple layers would be a nightmare to slash.

On the dremel at full speed it lasted an instant, multiple layers faired slightly better. Tested stupidly thick leather from a scrap moto jacket and I appreciate why leather is still king. Tried a piece of cordura, lasted even less time than aramid.

Pressed on the whetstone wheel spun fast, multiple layers faired very well, into the seconds at various speeds and pressures.

A silly-buggers test with two layers and my finger on the other side, after a second or two I had to lift my hand away because it was too hot, but only one layer had gone through and the other had begun to glaze.

Testing continues...

Anyone got opinions on all-weather riding on a naked bike?
I’d like something a bit more modern than my CBR (ie with a rain mode/some traction control) so I can use the car less to commute. Haven’t ridden a naked since passing my test and currently remembering the airflow in a very favourable way. On the other hand I also remember my first ride on a full-faired bike being a absolute joy!
PCP deals on BMW s1000r look very good...

Can't really speak for all weather as we don't really get it here. But my recent comparison between renthal, no fairing bike and new fairing bike is that I prefer the fairing for everything other than around town and VERY twisty roads. Renthal bike is more exciting...though most of that is lower gearing I think.

Those BMW S1000r / rrs look incredibly civilised given the performance. Pretty cool.

These are the worst incidents as you don't know what you did/happened.

Glad you aren't hurt and damage minimal. Hope the mind gremlins don't effect you.

You youngsters have no idea how good you have it ;) In my day you had some amazing continental milemaster tyres that were long lasted, with no fucking grip whatever the weather ;)

Cheers boss. The mind gremlins I can handle as they'll eventually go, it's the small scratches to my swingarm that will keep me up at night.

I do wonder if it's just the last segment of my commute home (through town on slow, narrow roads) that's skewing my viewpoint. Most of my riding is relatively traffic free and speedy but arriving home tired and cooking every day isn't ideal...
I've booked a test ride to investigate!

I've heard all the stories from the old boys at work (and my dad)... Riding home pissed and missing a turning and ending up half way across a field, 3 lads sharing a bike home, mole grips on the gear lever, the test consisting of a bloke with a clipboard running down alleyways between streets, jumpers for goalposts etc etc etc ;)

Edit: and they all had a CZ150!

Looking forward to a few more canyons Saturday morning. I’m thoroughly enjoying my new old motorcycle. Not enjoyed tarmac as much for a long time.

a few more canyons Saturday morning

We need photos

Canyons north of Malibu are amazing places to ride.

Couldn’t keep up with @Jung in my only trip up there though.

Small update on the GN125 saga. I believe that I have found and remedied the cause of the running problems.

Recap: from cold would start on choke then drop shortly and sputter and could stall out unless dropped to half choke or less, and even warm was idling bad under 2k, was lazy off the throttle, occasionally stalled out when idling or (engine) braking to a stop at a junction, seemed like a lag in throttle response, and most recently 50/50 refused to start up after parking when warm.

Seemed like a lean/rich issue but spark looked okay. Battery health fine. LED lights so limited load on electrics. Maybe a dirty carb so cleaned it yet again. Could have been tight valve clearances so not enough opening when hot, but when checked they are bang on spec. Was also suggested could be poor compression and possible rings need replacing. Do not want that.

Rings made me thing o-ring. O-rings, the donor carb. Donor carb with wrong sized jets and needle had a plastic o-ring type cap on main jet needle. Mine never had.

So since ownership in November I have never managed to work out that the issue was a bastard o-ring missing from the main jet needle has been absent. Part #32 in this diagram. I assumed that it was complete, since it was running but running poorly.

Took the grey one off the other needle shown in photo (correct needle is lower one missing it).

Result:

Choke start nice fast 3-3.5k rpm steady and no drop after a minute or so. Dropping to half choke a clear change in revs, and steady idling at 1.5k-ish when warm. 30-odd miles in very warm British weather and there is a positive response from the throttle, it seems to have remedied the lag and laziness, and the bike starts up when hot. Might be jinxing it, but hopefully that’s the issue sorted. Could probably get it idling under 1.5k at maybe 1-1.2k. Phew.

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In fairness, you were piloting an aircraft carrier through a class 5 rapid... :)

Ha. You’re not wrong there.

Would definitely have preferred an MT09 or a panigale.

Fun regardless.