RS rear wheel cush drive donuts

[F5 Dave]

Hi all

Almost forgot this with everything going on.

Grumph is making some more but experimenting with a new version that will be softer than the previous ones which were perhaps a bit hard once the metal inners were added.

He doesn't really want to be chasing orders & wants someone to buy the batch & sell them out as required as one has to buy a length of material.

I've kind of slotted into this role although a larger user is welcome to take the stand & I'll buy some off them.

We've yet to get a price sorted out, but can I have a roll call of people interested in buying a set or so.

{edit} Looks like $25 a set which is what you might call cheap compared to the alternative.

[speedpro]

1 set please

[Yow Ling]

i better get some too

[Buckets4Me]

yep thanks dave

[kel]

If the price is OK I'll take two set. Can get them out of the states fairly cheap but would prefer to get them locally.

[Rick 52]

Yep a set for me if the price is ok, cheers Dave

[Grumph]

If the price is OK I'll take two set. Can get them out of the states fairly cheap but would prefer to get them locally.

Steve Ward told me the other day he uses genuine on his fleet - at $15 each...Pretty sure we'll be nowhere near that expensive.

The materal supplier cocked up the order and it's arriving today - approx a week late - so the test set will be off to Dave Monday - PM me a postal adress Dave please.

[richban]

Yep a set for me if the price is ok, cheers Dave

x2 maybe more if cheap

[SS90]

Hi all



Grumph is making some more but experimenting with a new version that will be softer than the previous ones which were perhaps a bit hard once the metal inners were added.



I used the old red ones for 4 seasons, on 2 different RS125's and even me weighing in at 80 odd Kgs, they outlasted the original ones by a mile.
I can't actually recall ever having one of the red ones fail, but the original Honda ones did.

[crazy man]

I used the old red ones for 4 seasons, on 2 different RS125's and even me weighing in at 80 odd Kgs, they outlasted the original ones by a mile.
I can't actually recall ever having one of the red ones fail, but the original Honda ones did.same here made some for my zxr400 after market rim . used for 4 years and still fine . just got to make shore there a good fit not to lose

[Grumph]

I used the old red ones for 4 seasons, on 2 different RS125's and even me weighing in at 80 odd Kgs, they outlasted the original ones by a mile.
I can't actually recall ever having one of the red ones fail, but the original Honda ones did.

Now there's an unexpected testimonial...thanks.

i want to try them without the inner steel bush as Steve reckons they're too stiff. Removal of that should soften them up quite a bit and I'd be surprised if a bucket makes the torque of an RS125...

[quallman1234]

I'm in. HRC ones last about a season and priced at something crazy like 20$ each. Couple of sets for me.

[F5 Dave]

$25 a set of 3 at this stage.

[kel]

$25 a set of 3 at this stage.

can't argue with that! :niceone:

[RDjase]

:niceone:2 sets please

[F5 Dave]

Well I'm marking them up a cool 33 cents ea to cover a plastic bag or whatever, consequently after the testing is done we'll collect some money & make them as I haven't got too much spare to bankroll them & they should pop out pretty quickly, but we'll run them at the next meeting (28th) & see that they are sweet (as much as we can over one meeting). So gives you a month to put aside the readies.

Actually I'll need to see if I can get away with envelope posting for width.

I'll PM everyone a bank account & delivery date once we have test done. Give me your address when we get to that stage.

[richban]

but we'll run them at the next meeting (28th) & see that they are sweet (as much as we can over one meeting).

I might be doing some riding before then if you want more testing. Dyno and track day before the 28th with new engine.

[F5 Dave]

ok, I might have to drop em out & kick some tyres in your 'garge.

[richban]

ok, I might have to drop em out & kick some tyres in your 'garge.

Beers cold.

[F5 Dave]

I'll txt you when I got em.


Ohh beer. Time to go home & crack one.

[F5 Dave]

ok well I got em in my hot little hands. Look fairly stable but can squeeze them a bit by hand which is probably the right amount to provide some cushioning without sacking out.

Rich are you going to the track this weekend, or I might make it into town.

[richban]

Rich are you going to the track this weekend, or I might make it into town.

Not unless some kind person with a key invites me. Might have to join up and get a key myself.

[F5 Dave]

Oh yeah as an update the prototypes are fitted to my wheel & have done a few practice laps & a dyno session. Will do a race meet this sunday so I'll pull them out & check if they are all good & we'll be into supplying them, so put some pennies aside.


As an aside, who knows where to get RS125 front wheel circlips to hold the spacer captive? I'm missing a set for my wet wheel & as the spacer is unique for it it would be good. I have E type sets, but they are no good. [edit] http://www.bearingandengineering.co.nz/shop/BEARINGS/General/Internal+And+External+Circlips.html but $10 min order so I'll add some stuff. Best I measure the other ones., think its 25mm ext & 33 int

[F5 Dave]

ok all the first set seem to have survived just fine as far as I can tell with limited running, but I did have to tap them into place as my sprocket bolts were a little off & no damage occurred so I think they will be just fine. They are a little harder than the rubber but without the steel insert should be a similar cush effect.

Good timing too as my old Honda ones fell apart as I was changing them.

ok so I'll PM everyone my bank account, as I'm making no money on this and I've had a bit of a spendy crisis and hence no real spare float it will be a cash up front ordering system one run at this stage.

If you haven't received a PM & want some then PM me. $

$25 a set of 3 + $2.10 postage per order & don't forget to PM me your bank account name & address. Or no postage if you want to get them from me at the next bucket meet I'm at.

[F5 Dave]

ok rattle your daggs guys. So far I have payment for. . . 2 sets.

[Yow Ling]

ok rattle your daggs guys. So far I have payment for. . . 2 sets.


err yer, better get my shit together then

[RDjase]

ok rattle your daggs guys. So far I have payment for. . . 2 sets.

Shit, knew there was something to do, will transfer some $ shortly

[F5 Dave]

ok production has started. ;)

[speedpro]

$$ transferred tonight

[F5 Dave]

Sweet thanks, first batch made & more material being sourced today I am told.

[F5 Dave]

Ok they're heeerree.

Just bagged them up, hope to find some time to address them & get to the post orifice tomorrow, but can't promise. Rich & Kyle have them for when I see you.


There are 2 sets in stock & that's it.

[RDjase]

Top marks !

How many sets got made?

[F5 Dave]

18 sets all up. I bought a couple, a couple left over so 14 sets to racers.

[F5 Dave]

OK all taped to card, & sent today by snailmail. Should have them by weds I expect.


If I get enthusiastic enough & have some cash next year I have enough hex ally to make a run of gear linkages, but I'd have to buy a reasonable qty of good quality rose joints to make the freight worthwhile. Would have to sell a few to make it economical, but there are enough crappy linkages out there in the racing world it wouldn't have to be a bucket thing.


That might get me over the sting of the $43+gst left hand M6 tap. Would have to cut them to length at order time.

Meh, not sure if I can be bothered. Still I can't justify buying that tap just for doing a couple of myself. I have enough joints & left nuts for two.

[speedpro]

left nuts for two.

Geez, bet that hurt

[Grumph]

Just a hint to donut purchasers.

When you buy urethane suspension bushes, they come with a small container of a graphite based lube...

Something similar used on these will extend life noticeably.

[Buckets4Me]

got mine thanks

[Rick 52]

They have arrived, Cheers Dave

[RDjase]

Got mine thanks Dave

[jasonu]

:Oi:Still waiting for mine

[F5 Dave]

Yeah I don't like increasing my chances of winning the lottery by entering. If you want some you can pick them up when yer here.

[Henk]

Dave

Have you got any of these left?
If so let me know and I'll take two sets if you still have them in stock.

[kel]

Henk
I also asked Dave the same question, answer was no.
Try these guys - TSR world, approx $9 each http://www.tsrworldwide.com/
There's a couple of us wanting sets so let me know and we can combine shipping

[chrisc]

There's a couple of us wanting sets so let me know and we can combine shipping

Count me in

[kel]

Count me in

I was :laugh:

[Henk]

Bugger
I was hoping to get this sorted without ending up buying stuff overseas as a bulk buy using a PayPal account that I don't have. Will leave it a week or two for now.
Wonder if there is enough interest to get another local production run done.

[Bert]

PM Scott. He has stayed out of this given others were doing it; but if there is no one then I'm sure he will be interested in stepping up. He made all of ours...


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[F5 Dave]

Yeah they were ok but didn't last as long as they could have cause of the lack of inner. Cost to add them would be same as standard

[Grumph]

Henk
I also asked Dave the same question, answer was no.
Try these guys - TSR world, approx $9 each http://www.tsrworldwide.com/
There's a couple of us wanting sets so let me know and we can combine shipping

Sad to say Dave's right - steel inner would bring them close to this price from me.

What about scott ?

[Rick 52]

Sad to say Dave's right - steel inner would bring them close to this price from me.

What about scott ?

when the red ones started to wear i inserted copper tube around the bolt head, Its refrigeration pipe 1/2 inch i think, any refrigeration guy would have a off cut... thinking about it i might of expanded the pipe to fit, anyway they are still working well now .

[F5 Dave]

Part of the problem is the NF4 spacer wobbles so much that it kils the cush donuts. I'm going to try talk Sketchy to make some HHybrid NX4 type

[Gigglebutton]

I can make a mouldand get LEP to knock them out if enough people want them.

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[Grumph]

Part of the problem is the NF4 spacer wobbles so much that it kils the cush donuts. I'm going to try talk Sketchy to make some HHybrid NX4 type

That would have to be a large part of the problem....that sort of thing will kill the donuts regardless of whether they're rubber or urethane.

If that can be fixed - at reasonable cost - donut life shouldn't be a problem.

[richban]

That would have to be a large part of the problem....that sort of thing will kill the donuts regardless of whether they're rubber or urethane.

If that can be fixed - at reasonable cost - donut life shouldn't be a problem.

I run a Vortex sprocket carrier and had the same problem. They need inserts like the rubber ones.

[Grumph]

I run a Vortex sprocket carrier and had the same problem. They need inserts like the rubber ones.

OK - the problem with the OE rubbers on the NX4 125's was very short life. Probably due to wobbly sprocket carrier...So stronger urethane donuts with steel inserts solved that problem - roughly tripling donut life...BUT the feedback from among others, Steve Ward was that they were too stiff and may even have been a reason for some gearbox probs he had...

SO - when i was aked to do some for buckets, I told Dave - and others too - about this and suggested no steel insert as this made them much more compliant.

Speculation....the harsher torque of 4 strokes like yours Rich, may indeed require steel inserts. The more violent speed changes of Kart tracks Vs big circuits may add to this too.
What i will point out is that among my previous experience with urethane donuts in this application was a GSXR1100 with all the fruit and on Alky - using Marvics - and with some guy called Holden pulling the string....5 donuts in the rear and in two seasons, no wear. No steel inserts either....I will admit that the Marvic sprocket carrier was a high precision piece with zero wobble.

So - whoever does them should probably put in inserts - and ask for feedback.....

[richban]

OK - the problem with the OE rubbers on the NX4 125's was very short life. Probably due to wobbly sprocket carrier...So stronger urethane donuts with steel inserts solved that problem - roughly tripling donut life...BUT the feedback from among others, Steve Ward was that they were too stiff and may even have been a reason for some gearbox probs he had...

SO - when i was aked to do some for buckets, I told Dave - and others too - about this and suggested no steel insert as this made them much more compliant.

Speculation....the harsher torque of 4 strokes like yours Rich, may indeed require steel inserts. The more violent speed changes of Kart tracks Vs big circuits may add to this too.
What i will point out is that among my previous experience with urethane donuts in this application was a GSXR1100 with all the fruit and on Alky - using Marvics - and with some guy called Holden pulling the string....5 donuts in the rear and in two seasons, no wear. No steel inserts either....I will admit that the Marvic sprocket carrier was a high precision piece with zero wobble.

So - whoever does them should probably put in inserts - and ask for feedback.....

Another thing that adds to the wear is flogged out wheels. Oval hole that the rubber goes in. Mine are not to flash so would have helped shorted the life. I did prefer the feel of the bike with the urethane over the rubber. I would run them again. It would be interesting to try with inserts.

[quallman1234]

Using a Taloon Style Sprocket carrier versus the standard HRC sprocket carrier. Doubles the life of the donuts.

We have a few of these left as we did a run of them. If anyone wants to buy one. However, we never got around to doing the middle spacer, as it varies by application. I.e if RS wheels are on a different frame.
PM me if your after one.

[husaberg]

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