Motorcycle and Scooter appreciation

To come across as a cunt, I've had carbs go off and be vapour blasted and rebuilt by a pre cross flow guru. 1500 gt carb, at came back with the slurry from vapour blasting and the 'new' jets and air correction looked very used.

Is it a CV carb?

DOH needles is a CV carb, are the needles the same in both carbs is the float height right? Recent pissing about with carbs was cured by 'polishing' the float valve needle and seat with t cut and that cured a fueling issue. Not really sure how that helped but it worked.

Slide carbs by the by

Head bearings or fork.
Honda PCX. driving me insane. I'm over in Vietnam. Entire bike has been gone through multiple times (roads are much less potholed than UK BTW, hilariously so).
Head bearings, all of it, new by Honda, who have looked at it maybe 6 more times and keep saying its fine, its not the problem. BUT they refuse to actually take it apart and actually inspect. Get the feeling its like the crown race is not the right size, or is installed over the top of an old dust boot. On a road bike with old press in EC type cups, you get this exact sensation, no physical movement, perfectly smooth, never comes loose or needs adjusted, but you get this metallic rattle tappy tap on all uneven surfaces.

Fork, have upgraded with YSS PD emulator valve, as orifice tube damping was shite half a century ago and stock spring is too soft (average SE asian person is maybe 60 kg, i'm 85 + luggage + wife unit). Had it done by a suspension 'expert' who didn't drill out the old orifice compression holes so ride was like having a compression lock out on. Now rectified, but also have replaced lowers, bushs, glide rings, oil locks, seals again, tried various combo's of 'extra' washers between components like preload tube to spring, preload tube to top cap, spring to top of damper rod etc. Noise is still exactly same.
Fork performs now like a boss. Only 80 mm of travel, but sag is correct, damping is sublime for a scooter. Reasonable gravel roads are now 70 kph instead of 30 kph being basically out of control and unbearable.
Rear shocks put RCB VD+ which are preload, rebound and compression (slow speed compression adjustable only I suspect by feel) and have brought the rear end under really good control (for a scooter which has about as much unsprung mass as is possible with an entire engine, drive, cvt and assembly hanging off it).

But the noise is stll there. Have dismantled entire front of bike, all plastics off, riddden around, still there. Wrapped up ECU and other modules with old inner tube so that its impossible to make a sound. Still there. Did the same to fuel tank and just about anything else that was possible and stll the same. Cannot make the noise stationary, only when riding 5 kph +hippy

Noise is metallic, can feel it through frame and handlebars. Bike wonders at low speed 0 - 10 kph as if front wheel is going off line. Compared to a new PCX it feels fine for higher speed handling (30 kph+), but the low speed its twitchy and nervous. No brinnaling in head bearings detectable under any condition.
Changed the wheel bearings and spacer tube incase it was worn or incorrect.
Swapped parts with other used bike known good. Both wheels/tyre combo. Axles. Rear shocks. Entire fork legs from a bike that was not making the sound (damping and spring rate awful, but noise the same).
SO I'm very confident its not the fork legs. Only thing it leaves is new head bearings installed wrong or incorrect part. Dimension issue with crown race (should be whacked on there, could be loose or wrong part?). Or the axle to bearing reducers (little alloy top hats), feel fine, and if the axle is tight they surely cannot move, but maybe they can? Or actual fork crown/steerer tube has some kind of bizarre issue*

*Rock shox 2011-2014 basically all those forks are in the bin by 2017 as the steerer tube was swaged into the crown in the wrong dimension or tolerance or machine was worn = this comes loose and makes an annoying creak crack sound.

So yeah, driving me nuts. Lots of mechanics out here, but 99% of them are like 'well it feels smooth, and the bike rides OK, so what you complaining about?". Noise is loud enough a pedestrian can clearly hear it over engine and road noise if I ride past at like 10-50 kph.

Or someone is fucking with me and has put a bolt inside the frame and its just jangling away.

Theres a thread I found on stromtrooper forum (Suzuki) thats a possible.
https://www.youtube.com/watch?v=_32nl_FByU0

https://www.stromtrooper.com/threads/metallic-fork-rattling.433847/page-2?nested_view=1&sortby=oldest

PCX has a similar but more basic assembly. Outer chromed stanchion, but at the base there is a recess with a very thin metal guide washer held in by a smaller chromed piece of stanchion hydraulic pressed into place. Mine both rattle in all directions, but they did on the good used forks as well. I think their purpose is more to restrict the volume of oil that can attempt to blow past the damper rod (orifice tube type) at certain % of fork travel. I.e. as fork is bottoming out it restricts compression flow as the orifice tubes will have 'passed' by this slight restriction. And then when fork proper bottoms out the 'oil lock's' will receive into the bottom of the stanchions inner taper = oil is locked forming a hydraulic compression lock out = prevents total mechanical bottoming of the fork. Basic, but works for small size MC and scoot.

So could this be my issue? Only way to find out is buy new stanchions as they are not fixable like in the suzuki forum details. Or I'm barking up the wrong tree.

Always a struggle to find people who PROPERLY understand suspension in any country. Remember back in Scotland sending away my old bikes WP cartridges for service, they came back with just the worst noise and feeling over and over again, ended up totally loosing my shit with the guy. FINALLY found the issue. He'd mixed up one of the forks internal spacers with those from another fork that were just slightly shorter, so the damper cartridge had a tiny bit of play before being engaged. But you could only feel it when on the bike and being ridden, dyno and by hand revealed nothing. Guy was a respected suspension builder in northern England and had to basically scream and stomp my feet at him telling him he'd done it wrong until he finally REALLY looked at the fork again, and then, we found the problem, no apology obviously, was a simple mistake, but yeah, will never forget that ordeal.

What type of bearings are fitted to the head set.

Is the bike disc braked and are the bobbins or brake calipers rattling? Does it go away if you brake?

Or something loose in the handle bars

Has the front caliper got the spring clip that stops the pads rattling. Only mention it because I don't have them on my GSXR and the pads rattle LOUDLY a bit like you describe.

No help to your issues whatsoever as I sorted glaze eyed over this, but how’s life out there? Were you at? I miss Vietnam summat fierce.

Very rainy here. I missed out on all the fun of flooded roads on the DR, because of work.

Managed to tear into the carbs again.

The CV carb was working but clearly lean on the idle circuit. I'd left the idle as-is but upped the main jet, and raised the needle to highest clip position, and it ran well, but obviously missed some power on the lowest revs where still a bit lean. It would stutter a lot on low revs until warmed up.

The (non-pumper) TM carb didn't work when I last removed it having messed with it.

TM has a new jet needle that it fractionally (1mm) shorter than the original damaged one, but similar FP taper. That taper is half the problem though I think.

I've upped the idle jet a couple of sizes in the TM, and put the larger main jet I know worked in the CV.

Above 1/4 throttle or so, all good. Idle all ok after turning in the air-fuel screw a tad. Stutter very difficult to ride around at off-idle to 1/4 (effectively 2k revs to 3.5k revs).

I had to run an errand which involved a test ride, and riding around a stutter at off-idle made for interesting riding in rush hour traffic. Idle was okay, an at 4k or above it was powerful as you like. Just getting over that 2k-3.5k bit in traffic was rough.

My money's on raising that jet needle to its highest clip. If that doesn't push the stutter out, then it'll be swapping the needle taper and starting all over again.

Its epic. Will be here a year total, option to extend to 3 years. Got some UK stuff to deal with at some point so can't be out here long term, but will be hard to go back. Place is just so much more social, people are happier, economy functions, food is great, drink is great, weather gets too hot for half the year, but you get used to being up at like 5am, then do an AC cafe snooze around middle of day like everyone else.

Bikes here are great, but none of the good ones are ever for sale. Most used car/bike dealers are epic level scammers, very hard to find decent bikes, cost isn't the issue, scammers charge same for junk as real sellers for decent bikes. Been trynig to find a decent super cub or dream 100 for months and keep getting on the receiving end of a scam or just shady junk over and over again. This is even with VN friends who can navigate their way around assholes and time wasters. Average joe here buys a bike new, and then rides to death, or in event of bike still working (old cup and dream) passes down the family. Normal people do not sell a bike that works hence why the market is so shady, your only ever buying crash damaged/rebuilt/chinese aliexpress chocolate engine rebuild specials/stolen/or just trashed bikes on the used markets. Its a different culture in terms of transportation.

Though private domestic cars are starting to become a massive problem. HCM is already chocked with car traffic, and GOV has spent 20 years demolishing ever more of the city to build more car infrastructure. Hanoi is going that way too, people buy cars, roads don't move, gov has to be seen to do something, so compo purchases the next swath of housing, flattens it and builds express way sized roads. Guess what, traffic still terrible.

There are a LOT of western dirt bike guys. Maybe buy a WR250 or KLX250 and go play in the dirt. But risk of injury higher, a bust wrist or collar bone etc = spring time is wasted.

Got the raising and dropping the wrong way round. Stutter was bogging, not lean->rich stutter.

Raised the clip a couple notches, dropping the needle. Feels much better now but I think having gone up two pilot jet sizes I should have only gone up one.

Still feels rich off idle, but a 5 mile test no bogging.

Hopefully on the lanes tomorrow I’ll know for sure.

Did this get sorted? My bet is on the cartridge emulators- I had an F650 that had them and it had a horrible rattle as the forks would chatter as the forks topped out on uneven surfaces. I think some of the conversions do this.

Some verrrry deep puddles and zero grip. Lots of spinning wheels.

Main jet is fine, idle is poor. Off-idle is still a bit boggy. Going down a pilot jet size next week and hoping that leans idle out enough without bogging as it comes onto main.

Great day even riding around a boggy idle.

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Scans from an old 'Gentlemens Journal'!

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It was the mudguard! Annoying as I'd spotted it ages ago and asked numerous respected mechanics about it and their answer was all firm 'no this is not your problem'.

Repaired mudguard with araldite and some wire to enforce it. Mudguard is also the fork brace as its a short travel single crown scooter fork.

Fork and shock now feel basically bottomless, pretty good for 85mm travel. I knew it could be achieved despite most folk constantly saying 'just buy a CB500x' (the only big bike thats easy to buy new/used and is legit on paperwork), which of course has orifice tube dampers too.

Emulators are great. Change the oil weight for rebound, fiddle the compression adjuster for low speed compression adjustment, high speed is blown off by the weight of the spring/size of the holes in the metal piece. Wont' fiddle with it anymore, does now exactly what I want it to do which is make an under powered midi scooter tolerable for 8-14 hour days.

Dropped to the smaller pilot jet (one size up from OG) and it was riding better but felt heavy and boggy. Felt like it was blubbing through fuel without a strong bang. Did a couple easy lanes but it just didn't feel snappy. Next to no popping on overrun, but a few burbles like excess fuel.

Back to the OG pilot jet that I knew was good. Quick ride to the shops and it felt really crisp and good. Not as much cracking on overrun as it had been before, so ideally that means I've got it running not-too-lean.

So, the TM carb now has the OG pilot, larger main jet, new (different) jet needle. I think the problem all along was the needle. Just swapping the main jet was never enough, I think the needle was all wrong.

We'll see by the weekend if it's good or not. Maybe I need to adjust the clip position to get it better still.

Doesn’t sound like regular loose tappets… too tinny…

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Definitely not the plan. First lane. First puddle. First blood. That’s his knee fucked for a while.

Paramedics learned how to drive automatic ambulance offroad… Only 100yd but must have felt like 10 miles for the poor driver.

That concrete block he’s sat on, he got it wrong through the puddle and slammed into it. Bike, concrete and knee sandwich. I’d probably have cancelled riding if I knew he didn’t have the hard armour yet. Apparently it wasn’t delivered, so he had the soft armour on.

So. Within 10 minutes of starting, I was calling 999, and calling the motorcycle recovery friend too. Whilst shouting at this mate not to try to move.

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Yikes. Sucks. It happens. Poor guy.

Here we are very set up for rescue, 4x4 ambulance, helicopter service etc. Feel blessed.

If we’d been further down it would have needed the £££ air ambulance or a 4x4 for sure.

One of the benefits of paying for my inreach is the rescue costs insurance.

Air Ambulance here is covered by donations from people like you or me, so they will respond to 999’s like a regular crew. I was just glad it didn’t come to that. If it had been that bad, well, I’m glad he stayed conscious.

Yeah. Hope he makes a good recovery. Knees are complex!

“Femur broken in two places going into the joint and knee cap shattered. They’ll operate on me tomorrow.”

He’s off for a CT scan now.

Better than the tibia, should make a reasonably quick recovery. Fingers crossed.