revtothelimit - motorbike forum

To be honest I reckon the misprint is as simple as making 11.0 into 21.0 and 11.5 into 21.5. That ties in with the owner's observations in your post. For most folk something in the order of 9.0 or 9.5 N/mm would be about right.

And no-one purchases springs on the basis of weights/rates combined. You order a pair of springs rated at x.xx N/mm each. Last month I ordrered a set of softer fork springs for my Duke 690 R from Springcoil. I specified the rate per spring (6.1 N/mm, as it happens) and that was understood and accepted. You don't complicate matters by multiplying spring rate by two, just so they have to divide by two to arrive at the actual spring rate.

That would be silly. And not in a good way.

mangocrazy wrote: Sat Mar 06, 2021 8:35 pm To be honest I reckon the misprint is as simple as making 11.0 into 21.0 and 11.5 into 21.5. That ties in with the owner's observations in your post. For most folk something in the order of 9.0 or 9.5 N/mm would be about right.

Sounds right to me too,but some cartridge designs work differently. (topout springs,etc)

Skub wrote: Sat Mar 06, 2021 8:37 pm

mangocrazy wrote: Sat Mar 06, 2021 8:35 pm To be honest I reckon the misprint is as simple as making 11.0 into 21.0 and 11.5 into 21.5. That ties in with the owner's observations in your post. For most folk something in the order of 9.0 or 9.5 N/mm would be about right.

Sounds right to me too,but some cartridge designs work differently. (topout springs,etc)

Yeah, I get that, but the spring rate is a value determined by a combination of bike weight, rider weight and intended application/rider preference. Top out springs don't change that to any appreciable degree.

mangocrazy wrote: Sat Mar 06, 2021 8:46 pm

Skub wrote: Sat Mar 06, 2021 8:37 pm

mangocrazy wrote: Sat Mar 06, 2021 8:35 pm To be honest I reckon the misprint is as simple as making 11.0 into 21.0 and 11.5 into 21.5. That ties in with the owner's observations in your post. For most folk something in the order of 9.0 or 9.5 N/mm would be about right.

Sounds right to me too,but some cartridge designs work differently. (topout springs,etc)

Yeah, I get that, but the spring rate is a value determined by a combination of bike weight, rider weight and intended application/rider preference. Top out springs don't change that to any appreciable degree.

Have a bonus point for that. Most folk forget the weight of bike to be added to the rider.
The rider becomes less significant.

mangocrazy wrote: Sat Mar 06, 2021 8:35 pm That would be silly. And not in a good way.

Well yes, but it would be equally silly for Kawasaki engineers to neglect that all important factor of 2 when designing the bike

At the end of the day its totally arbitrary which way its quoted. I have no idea what the norm in Japan is.

Mr. Dazzle wrote: Sat Mar 06, 2021 9:08 pm

mangocrazy wrote: Sat Mar 06, 2021 8:35 pm That would be silly. And not in a good way.

Well yes, but it would be equally silly for Kawasaki engineers to neglect that all important factor of 2 when designing the bike

At the end of the day its totally arbitrary which way its quoted. I have no idea what the norm in Japan is.

I suspect that the vast majority of people who buy one won't give a flying fuck about the spring rate as long as it looks good.

Doesn't float my boat, I'm a bit too much of a luddite, but I suspect Mr Rea will sell loads of them.

Bigjawa wrote: Sat Mar 06, 2021 9:16 pm I suspect that the vast majority of people who buy one won't give a flying fuck about the spring rate as long as it looks good.

But those poor marketing guys spent ages writing the press releases in loving technical detail

Its a type by MCN, but do you expect anything else from MCN. I cringe at some of their reviews when they get technical..! I was supposed to do an article with one of their guys a couple of years back but the editor decided it was not the 'in thing' at the time even though the journo really wanted to try get some education to the masses on more than just setup.

21.0N does not even exist and I think the heaviest rates are generally on the Aprillia's as some of them have 11.5N as stock. If this was not a misprint then it just shows how untechnical the composer actually is, journalists are that for the most part. I have a very good friend who is an engineer turned journo yet not a single bike mag will give him a shot, they are all too busy in peoples pockets getting free gear and writing reviews that puts the perks in their pockets-I never buy magazines these days they all have biases!

The stock springs in the new bike will no doubt be the same as last year as the fork is the same and the weight of the bike is not really much different, the list somebody shared with Kawasaki suggested rates is not too bad. I can get far more in depth with how I calculate it, but if your riding on the road being in the ball park is fine. Again, if your 20 odd stone underestimating the benefits of the correct spring rates is a mistake, stock suspension for the most part is cheap and sometimes does not even work..! (adding stiffer springs can sometimes highlight how under damped some systems really are).

Bike prices are taking the preverbial now, it has just cost my team over 30K for a stock BMW S Thou RR with discount (for which they had to buy 6), thats before we have to build it to BSB spec and start adding BSB Spec electronics and ECU's... It is no secret that the new ZX10R was built around Rea so that it could be contested in WSB, that is why it is so aggresive in its makeup.

As somebody stated, and I see this from the perspective of what I do... Many people dont give 2 hoots how bad or good something is if it looks good. More people waste money on flash tuning and power upgrades or they allow themselves to be sold into something because some vlogger/blogger said it was amazing. Yet dont even conside handling (tyres and suspension) I think I upset the last vlogger who wanted to do a video with me, I still would not want a modern superbike for a road bike. But each to their own, haha.