Cerbera's Master V2.5 thread

[Cerbera]

Thanks for looking / listening.

1 hour ago, Paul A said:

Perhaps when the wheel is leaning, the tyre then rubs against something.

 

1 hour ago, Paul A said:

Perhaps the axle has not been sufficiently tightened, and there is movement in the alignment of the wheel, when going around a corner.

My thought also, but in this service I didn't remove the motor so the axle hasn't been touched, nor any screws in the hangars other than the ones that remove the pedals.

1 hour ago, Paul A said:

Maybe the maintenance disassembly/reassembly has been the cause of things changing.

I would have to agree, given its perfect performance before it, but I just can't think what I could have done wrong - I only took the sides off, moved the batteries aside so I could clean the bearings outers and the top cover so I could inspect the mainboard ! All went back together exactly as expected, so I am mystified as to what could be so suddenly and big stylee wrong...

In my extended tests it seemed less connected to cornering than it was to hard forward leans. Would that tell us anything ?

Edited March 30, 2023 by Cerbera

[Paul A]

Perhaps first try and determine if it is the tyre producing the noise.

Maybe inspect the sidewalls of the tyre for groove marks.

Perhaps rub a chalk line across the tyre sidewall, on both sides, from rim to tread.......any scraping across the chalk line will indicate where the friction contact location is.......can then simply rotate the tyre and see where the 'missing chalk line' passes the casing.

Don't need to chalk the entire sidewalls.....just a line will suffice.

 

 

Edited March 30, 2023 by Paul A

[Cerbera]

Well, I convinced myself it couldn't possibly be the tyre, that spins freely no matter what the lean angle / load / suspension pumped or empty.

So I have decided to see if what Speedyfeet's engineer suggested I do back when he sent me the replacement charge board, and pump a whole load of silicone sealant between the lowest 2 mainboards, to try and eliminate vibration between 1st and 2nd level boards. The noise in Video 2 above really was quite like that I thought, and having ruled out tyre rubbing and anything to do with suspension, this seems like a reasonable thing to try.

It is really VERY difficult to get the silicone in there, even with a nozzle, and aiming it under the big 2 main capacitors makes it very difficult to see how much has gone in.

But anyway, I have done it now, and just have to wait til tomorrow for that to set and to find out if that has fixed anything. If not, I am totally out of ideas...

[Rawnei]

What wait, silicone sealant between the stacked mainboards?! What is the purpose of that?

[Cerbera]

It apparently stops vibration between top and bottom mainboards, which can lead to (possibly) the sort of noises / juddering I have been getting, which we can hear in my video above, and the second of the 2 that @Paul A posted. Begode realised / addressed this is the batch after ours by including a silicone gel pad between the 2 boards. But I had silicone, and a video of the tech guy doing his, so took his advice and copied him !

Edited April 1, 2023 by Cerbera

[Rawnei]

13 minutes ago, Cerbera said:

It apparently stops vibration between top and bottom mainboards, which can lead to (possibly) the sort of noises / juddering I have been getting, which we can hear in my video above, and the second of the 2 that @Paul A posted. Begode realised / addressed this is the batch after ours by including a silicone gel pad between the 2 boards. But I had silicone, and a video of the tech guy doing his, so took his advice and copied him !

Damn sounds rather messy but I hope it helps.

[Cerbera]

Just now, Rawnei said:

Damn sounds rather messy but I hope it helps.

Me too, my friend, me too ! My hopes aren't high TBH, but it's the last thing to try before I am totally out of ideas and have to send it back to dealer for repair.

[Paul A]

If it is the tyre, the chalk will rub onto whatever it is making contact with...... identifying the position.

Perhaps rub plenty of chalk onto the sidewalls to make any contact more visible.

Perhaps search YT for more videos on Master noises.

 

Warranty will cover any repairs anyway?

 

 

Edited April 1, 2023 by Paul A

[Cerbera]

48 minutes ago, Paul A said:

If it is the tyre, the chalk will rub onto whatever it is making contact with...... identifying the position.

I am 99% certain it is not the tyre - there is a clear 5mm of space either side of it, whatever angle the machine is at.

 

49 minutes ago, Paul A said:

Warranty will cover any repairs anyway?

I hope so. We are still in Year 1...

[Paul A]

Begode master vibration noise

Herbert DaSilva

Oct 19, 2022

 

[Cerbera]

Yep, thank you - that's the same guy as the first time right ? That is pretty much identical to the noise I am getting.

My silicone is 12 hours into curing, and I tried a quick roll around the kitchen, which was silent, but then it always was, hopefully tomorrow the rain will have abated and I can see if my attempt has been successful or not.

[Paul A]

Yes, same person.  Videos were uploaded on the same date too.

From the comments, seems that the silicone spacer worked.

Silicone cure time will vary depending on the thickness.

Cure time could be up to three weeks.

[Cerbera]

6 minutes ago, Paul A said:

Cure time could be up to three weeks.

Well I'm damned if I'm waiting 3 weeks to try it !  Box said 24 hours, so I'll give it that. Although I also squeezed some onto some card at the same time so I could monitor the curing process. It's pretty solid even now.

[Cerbera]

O.M.G.

Despite having almost zero faith that it would, it 'appears' that my 'Heath Robinson' silicone fix has worked - just did 10 ups and downs of the driveway and a small local loop, which definitely would have exhibited the noise had it still been there, and it wasn't. I sort of can't believe my luck, so have come in to have a calming cup of tea before suiting up properly for a bigger test ride.

[Cerbera]

Yep, whatever that was, the silicone has fixed it and I couldn't be happier. 12 km ride complete, and not one single instance of the horrible noise ! Once again, it's a total victory for forum-ing, and tech support - within minutes of posting @Paul A had found a video that exhibited the same noise, that video also contained the solution, as did the video Speedyfeet's tech sent me a month ago with advise to manually silicone the gap there while I installed the new satellite and charge boards. I didn't do it at the time because I didn't have the problem.

But something I did in the 1000 mile service changed something about that board, and I still don't know what - All I did was check it was seated firmly, and go around tightening screws and checking connectors, so that may remain a mystery. However, I did find one screw on the front of the mainboard that is just free spinning indefinitely - there seems to be no, or worn out thread in the case under that. I silicon-ed that too, and I think I am happy for the remining 3 screws and the thermal pad to firmly fix that to the base of the case. It certainly feels very solidly mounted, and the ride today would seem to testify to that being OK, for now certainly, and possibly in the longer term ? Time will tell ! Meanwhile very happy little bunny over here. 

Also, calibrated my machine again, this time to level, from the -3 degrees it was form the factory. WOW !! What a difference to acceleration !

Turns out the Master is EVEN MORE of a beast than I thought it was !! Braking has got correspondingly (and not a little worryingly!) longer, but I have adapted quite quickly, and I have moved power pads a bit closer and higher on my leg so it gets applied harder, quicker. Ride Mode 2 still fine for now, but will try 3 again tomorrow. TBH I only ever left Mode 3 in the first place because acceleration was so difficult up hills and trolleying forwards was such an effort !

Edited April 2, 2023 by Cerbera

[Cerbera]

Here she is, being successfully held in repose by @Rawnei's enhanced stand, which I trust to hold it on uneven ground, right next to a lake in a way I definitely wouldn't with the stock grommets !

[Cerbera]

Just making a quick record of what I did / found in the 1000 mile service...

During this service I was aiming to address the following potential 'issues'

• Investigate recent 'crnk' noise that has started appearing when suspension reaches its extremes
• Check condition of battery packs and tabs connecting to mainframe for cracking / damage
• Re-check main wiring / waterproofing / seating of new charge board and satellite board / check for signs of water / dirt ingress
• Inspect motor cable for flex damage.
• Check and re-tighten any loose screws

General notes:

• Plastic battery cases are almost unblemished ! The top and bottom sections are not at all cracked or damaged yet, and the inside of the cases seems to have experienced only the lightest of scratches from detritus passing over them, and no serious dings from stones or twigs whatever on the inside facing surfaces. I think we may have been too quick to judge the use of plastic here - in mine at least, so far, that is proving 'adequate' and structurally robust in the (vertical) direction of stress. The fact that you can flex those packs when empty (often held up as demonstrating their 'Happy Meal quality') is all but irrelevant. I think the Grizzla fairings have done a very reasonable job of protecting the outside of the packs, and I imagine that the solid bridging blocks between the fairing and the batteries may well have helped strengthen, brace and protect those tabs from cracking, and if so is a further thing to thank them for !
• So undamaged are those battery packs I am not even going to fit the metal plates I bought thinking they would need the extra protection. I note I would still prefer that they were metal, but I am less worried about the plastic cases than I was.
• Quite a lot of accumulated forest floor stuck to my re-greased bearing covers and surrounding areas, as expected. Dug that out, cleaned it all up. The bearing covers were intact however, and had not lifted, which was something I worried about briefly after replacing them after the re-grease. Did not add more grease, except for the thinnest of layers to the bearing cover to further try and repel water. Ride today was SO much quieter than it was - all that crud was obviously rubbing and making excess noise at speed. Pleased it wasn’t the bearings themselves that had gone ‘grainy’.
• All screws have held tight, including all the battery back ones, none of which were threadlocked. In order to prevent undue stress these were only hand-tightened, but the spring-clips there have held them perfectly in place - none had shaken loose..
• Motor cable is not showing signs of excess fatigue - sleeving remains clean and intact, and is still held firmly in place by retainer screws.
• Pedals bars were re-greased after cleaning the pedal blocks
• Grizzla bolts were checked for rust and blocks for cracks (none found) and re-attached with new adhesive pads
• Shock pressure checked and found to be down a whopping 60 PSI from its previous level of 210, which might explain crunking / bottoming out recently ! In the 500 mile service it had lost no pressure at all, so not sure why it has suddenly gone leaky now. Will monitor that, and check weekly from now on.
• Tyre pressure checked and found to be unchanged at 23 PSI
• Suspension linkages and shock are fairly filthy. Cleaned and dried.
• Battery packs were inspected for water ingress (none found, Gaffa tape seals holding)
• Hub silicone seal inspected, still intact, but looking a bit rough in places. Will re-apply at next service (1500 miles)
• Silicone seals checked on all battery packs. All seems fine.
• Seals checked into mainboard / charge compartment / looked for signs of water / dirt ingress - none found. No cables trapped, or loose. All boards secure.
• Calibration checked, and found to be WAY off ! At least 3 degrees reverse bias I reckon, which might explain why acceleration has been not exactly a struggle, but less angsty and ‘raring to go’ than I have been led to believe it might be by watching everyone else on theirs !

Reset to exactly level using EUC World and this spirit level.

• Internal wiring check revealed one small hole I had forgotten to plug (where headlight wire comes in), so did that.
• New charge board trailing lead was coming perilously close to being trapped in the case, so tried to mitigate that. Was not worn, so foam did its job there.
• All rubber gaskets intact and not perished.
• Visually inspected the metal brace bridge for suspension sliders. Not cracked or showing signs of distress yet, but didn’t fully dismantle, so have not looked everywhere.
• My old multimeter has broken, so have ordered a new one with which to check pack balancing.
• Remained with the knobby tyre, which I am now fully used to riding with and controlling its eccentricities. Love its grip, which is exceptional.

Of course, having put it all back together again I then found I had the vibrating mainboard issue, so had to open it all up again to inject a load of silicone between bottom and top mainboards to prevent case vibration reaching the gyros and producing an intermittent grinding sound during rides.

And otherwise, that all seems fine, my waterproofing plans seem to be holding up, so although I have to keep an eye on shock pressure (check weekly) I am going to award that a pass on the 1000 miles hardware check. Next full check 2000 or on next tyre change.
 

Edited April 5, 2023 by Cerbera

[Cerbera]

Now I've had the Master a good few months I am starting to off-road it a lot more, and as most of the off-road bits around me are in a series of wooded trails up the highest hills we have, I have decided tethering the Master is going to be a good plan after all. I've made mine out of the thick strap from a laptop bag, and a couple of short bungee cords, with 2 little break-away sections as shown below...

Initially I was worried about the weight of the wheel, and me being not much heavier than it, but now I have much better ride control over it I fear it less, and don't mind tying it to me. Having seen Dawn's recent EX-30 crash, where her machine was saved from all but cursory damage by her tether, I am feeling pretty confident this will arrest any 'spinning dances of death' that my Master may have in store for me.

[Cerbera]

Just a quick note to self that if you do insist on trying to go out on a Master when the wind is doing this...

...it won't be 'fun and challenging', as you might imagine; it will be sketchy-as-fuck and properly terrifying !

Blown into walls, blown into traffic, wrenched around corners, felled by cross-wind and straight-out blown over on the exposed bits. Good XP perhaps, but you couldn't call it 'enjoyable', especially when the stair-rodding rain joins in as well !

And also remember that if EUC World gets rained on, then all manner of weird shit and beeps start coming from the wheel if you forget to disable the touch input ! God alone knows how many settings got inadvertently changed today !

Edited April 12, 2023 by Cerbera

[Wheel Guy]

7 hours ago, Cerbera said:

Just a quick note to self that if you do insist on trying to go out on a Master when the wind is doing this...

...it won't be 'fun and challenging', as you might imagine; it will be sketchy-as-fuck and properly terrifying !

Blown into walls, blown into traffic, wrenched around corners, felled by cross-wind and straight-out blown over on the exposed bits. Good XP perhaps, but you couldn't call it 'enjoyable', especially when the stair-rodding rain joins in as well !

And also remember that if EUC World gets rained on, then all manner of weird shit and beeps start coming from the wheel if you forget to disable the touch input ! God alone knows how many settings got inadvertently changed today !

Wind is the raid boss of sketchy shit on EUC! Does your master fare ok in the rain?

[Cerbera]

3 hours ago, loofv said:

Does your master fare ok in the rain?

Well it does now, but I had to do quite a lot of stuff to it to make it that way !

Previously, however, the rain has caused me big problems, and it was shortly after I got caught out in that first rain storm that my bearings started knocking, and kept doing so until I did a full re-grease of the bearing races. So, yes, the Master does totally fine in the rain, on the condition that you have:

• Taped all the screw holes in the battery boxes
• Siliconed the rims on the motor hubs
• Re-greased the bearings (if needed)
• Blocked the 2 large holes into the mainboard case to prevent water ingress from below
• Covered the entire top of the machine with a waterproof backpack cover to prevent water getting near those vulnerable charge ports.

If you've done all that, then your Master can ride in rain all day !

[Wheel Guy]

14 minutes ago, Cerbera said:

Well it does now, but I had to do quite a lot of stuff to it to make it that way !

Previously, however, the rain has caused me big problems, and it was shortly after I got caught out in that first rain storm that my bearings started knocking, and kept doing so until I did a full re-grease of the bearing races. So, yes, the Master does totally fine in the rain, on the condition that you have:

• Taped all the screw holes in the battery boxes
• Siliconed the rims on the motor hubs
• Re-greased the bearings (if needed)
• Blocked the 2 large holes into the mainboard case to prevent water ingress from below
• Covered the entire top of the machine with a waterproof backpack cover to prevent water getting near those vulnerable charge ports.

If you've done all that, then your Master can ride in rain all day !

Thanks for the tips! I've done the battery boxes and some silicone, and I've let my charge ports "air dry" for a few days after riding in the rain lol. My bearings are surprisingly still fine, even after accidentally submerging my wheel in mud.

[Cerbera]

That's a good plan about leaving it to air dry before charging if it has got wet. Another tip is that if you do ride in rain and it does get wet, then do not leave it on its side where the water can run down over the internals - couple of people who have done that have had the Master drop them a day later, and there was that one report of the MB doing the magic smoke when charged whilst there is some water somewhere internally ! So air-drying while it leans upright against a wall is much better for it than charging it on its side (or stand) right after a wet ride !

But the $3 15L elasticated rucksack cover does a majestic job at preventing all water ingress from above, so if you have one, and it gets deployed early on while rain-riding then you can entirely circumvent all that drying-out business.

But if you know where these weakness are and take action to mitigate them / check them occasionally, it is a surprisingly robust machine in the end ! Of course it would have been nice if Begode has finished building it before it arrived, but hey ho, such is their way, and I love mine regardless - it remains one of the most exciting rides you can get 

Edited April 13, 2023 by Cerbera

[Wheel Guy]

Agreed! I love the master, although I feel the "extreme" will now make the master obsolete. I'll see about getting me one of them backpack covers

[Cerbera]

Right - time for an educational post now ! Much to my shame I have made an elementary error with my Master, caused (with the joy of hindsight) by my own lack of experience with MC tyres ! I post the whole embarrassing incident here in case anyone else risks falling to the same 'trap' !

For a while now I have noticed that my Master has started sounding quite 'grainy' as the knobby tyre moves over concrete surfaces, and I have been imagining that this is probably down to slightly less-than-optimal bearings, and the CST-186 wearing down to its natural profile, now I have over 1500 miles on it. It had become SO much easier control recently, which I had been attributing to improving skills !! Not the case alas...

Normally, and weekly, as has been, and I deemed 'sufficient' on all my previous EUCs, I have checked the general tyre pressure just with a quick squeeze of the wheel to check it is still as firm as I remember it being, and I have been doing that on my Master, and when I find it firm, I have not felt the need to actually check the pressure with a guage ! Well today I did do that, and was slightly appalled by what I found - I have been running on essentially a flat tyre for quite some time !! :/ Thank god it was leashed all that time, and I was wearing my armour !

The ramifications of this were suitably appalling - I have been regularly doing <55 kph on selected isolated cycle paths pretty much every day for the last couple of months, and if that tyre was truly flat, then the scope for it coming off the rim during the many speed runs, downhill hops, and little boops my wheel has encountered in the last 500 miles of riding, some of which has been very off-road and bump-intensive, would be pretty huge ! And we do know that Master's rim is a bit infamous for letting tyres fall off it !

Fortunately for me, I am very light, and I haven't done ANY big bonks, and sets of stairs at all, which is probably why I don't have any rim damage, but I still consider it somewhat miraculous that I don't ! 

So the lesson to be learned here, for anyone who may be reading and has their first EUC with an MC tyre...

An MC tyre feels firm to the squeeze even when completely empty !!! I am literally ASTONISHED that in my 8 years of constant reading of this forum and EUC experience in general that I was unaware of this until today !

Ok, so this raises another question. My grip and control over that machine was AMAZING while the pressure was gone ! And now I have pumped it back up to 20 PSI, and checked it holds there, it is skatey and tippy as all fuck and I hate it !! Immediately reduced PSI to 15, which was better, and controllable, but then had the most HORRIBLE wind ride into town and back, where I was thoroughly destabilized by the 27 mph gusting winds. I want my pressure even lower than that to reassert control properly !!

So, question for more experienced bigger EUC riders, what is the lowest pressure I can reasonably put in that tyre without risking rim damage. I mean I have a month of evidence that says the answer is 0 PSI, but obviously that can't be right !! I have, however, read about people riding their Masters as low as 10 PSI, and wondered if that was within reasonable margins ? What do we think ? What pressures do other Master / CST-186 owners go for, and how often do you check yours !?!

Edited April 19, 2023 by Cerbera