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Discussion Starter #1
For those that are running this fork upgrade. What do you weigh, what spring rate did you get and what info did you give them when ordering? I specified that I weigh 260lbs in full gear and the intended purpose of the bike is daily driving and hooligan antics. They sent me cartridges with 8.3 springs. I have been reading and reading, that seems like it is the base rate that they send out without any specific weight request. Is this correct? Is this spring the generic spec for my weight and intended purpose? I emailed them and they arent responding.
 

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I can't recall what mine were, but Andreani springs come as follows (Kg rounded up)

7.8 N/mm = .8 K/mm
8.3 N/mm = .84 K/mm
8.8 N/mm = .9 K/mm
9.3 N/mm = .95 K/mm
9.8 N/mm = 1.0 K/mm

Using the Racetech calculator (RT - Digital Product Search) your probably @ 0.95 to 1.0k/mm which translates to 9.3 to 9.8 N/mm. I'd put your own #'s in and see.
 

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It's also worth noting that the spring rates on mine were different in compression fork vs the rebound fork. @motowheels (where I bought them) said this was correct when I called about it.
 

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Gosh, I’m not sure about the Hyper. I think the long travel forks tend to run a little softer spring than most sport bikes.

But my experience with other bikes is that the .85 would be pretty soft for your weight.

I would start by finding out what the stock springs are and compare to that.

And running different weight springs per leg is just a way of fine tuning when you need 1/2 steps.


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For those that are running this fork upgrade. What do you weigh, what spring rate did you get and what info did you give them when ordering?
Installed a set of Andreani fork cartridges in my 2003 Honda VFR800 Intercepter. Told them I weighed 190 fully geared up and was using the bike primarily for spirited sport riding and occasional long distance riding. The fork cartridges came with 8.8 rate springs. Got my fork cartridges on Ebay from a seller called Omnia Racing.
 

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Discussion Starter #7
I bought them from https://www.bellissimoto.com and followed the directions 'put rider weight with gear in comments'. I havnt contacted Bellissimoto yet. I wanted to do a bit of research first. Is there a way to compensate spring rates by using shims?
 

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No. Changing preload with spacers or whatever does not change the spring rate. You can however make a stronger spring by making it shorter.

But best to get the proper rate to begin with.


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Discussion Starter #9
Is this something that they should swap out or do you think it's an additional cost? Have you had this issue in the past? Is it best to not install them at all until they respond, like, once they have been mounted they are non refundable?
 

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Is this something that they should swap out or do you think it's an additional cost? Have you had this issue in the past? Is it best to not install them at all until they respond, like, once they have been mounted they are non refundable?
I think the biggest issue with installing them is you gotta dig em out later.
 

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they're too light for a normal travel fork application, but with the hyper's extended travel the idea would be to allow it to be used, otherwise many would be upset. but if you spring it like a normal bike it will behave more normally in terms of pitch, etc. in terms of suspension the model is a victim of its fashion.

depends which way you want it to work. if you spring it to reduce the travel used you'd need to do the shock as well.

std rate is around 0.6 i think.

adding preload will reduce the sag. too much preload and they'll be harsh in the initial movement.
 

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Those springs are going to be too soft and as belter said, adding preload is not the proper fix and counter to what you’re trying to accomplish. Get the proper rate springs.
 

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If, IF the stock spring rate is around .6, then going to .85 is a BIG change.

It’s just possible Andreani knows what they are doing. A .25 spring rate increase plus better damping will make a huge difference.

As I said earlier you need to find out for sure what the stock spring rate is. If it is .6 I’d put the cartridges in as delivered and try it. Hopefully Andreani recommends an oil level as that’s also important if you’re doing wheelies and stuff like a good hooligan. :)


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Discussion Starter #14
One of the things that spike my concern is that another guy took advantage of the same sale I did. He also specified he weighed 160lbs in gear. He also recieved 8.3 springs.
 

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Yep. That sounds fishy.

Ok, do this. Let the other guy put his in first. If he complains about it being way too stiff for him you know it might be just about right for you. :)


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For comparison, 2012 Hypermotard 1100 Evo SP, 220 lb street/track Andreani cartridge came with 8.8 kg/m (86 Nm) springs and Race Tech shows stock is 6.6 kg/m (65 Nm) but haven't installed an setup yet.

Maybe speak with David Behrend at Fast Bike Industries (Andreani USA) to verify spring rate.
 

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I’m assuming this is a hm939 from your little pic? 181kg dry according to Ducati, with 220lb rider = 100kg, so call it 300kg loaded. 170mm fork travel, add 15mm preload = 185mm

the most load the forks will see will be standing on its nose with the back wheel in the air, 150kg per leg.

150kg / 185mm = 0.81kg/mm.

So, probably about right. Of course, the oil height induced air spring will have some impact, but if you want to use all the travel you’d need a spring rate in that area.
 

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I’m assuming this is a hm939 from your little pic? 181kg dry according to Ducati, with 220lb rider = 100kg, so call it 300kg loaded. 170mm fork travel, add 15mm preload = 185mm

the most load the forks will see will be standing on its nose with the back wheel in the air, 150kg per leg.

150kg / 185mm = 0.81kg/mm.

So, probably about right. Of course, the oil height induced air spring will have some impact, but if you want to use all the travel you’d need a spring rate in that area.
Are you sure it works like this? What happens when you factor in the fact that motorcycles can generate braking forces of 1.5 - 2 G's. Just asking.
 

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it's a rough guide my suspension man gives me when i ask him about spring rate. a gross generalisation, and air spring can have a massive influence too. most oil levels will give an air spring effect at full compression in the range of 30 to 50% of the spring load ime.

how does 2g under brakes translate into fork travel? at that point it's all on the front, rear wheel is certainly off the ground. but i don't think the fork springs would be seeing 2g.

certainly cornering will see high force. not on a hm on the road. i think 60 degree lean is 2g. certainly motogp territory, but not on the road. cornering load will certainly compress both ends and relatively too i would think.

overall, dunno. how else do you estimate required spring rate? show me the math.
 

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Discussion Starter #20
Could oil level/air gap offset the spring weight? Like, could someone who weighs 160lbs and another person who weighs 240lbs use the same spring rate by changing the air gap, or does air gap not have any impact of spring rate? I got a response from Bellisimoto. They said they weren't sure about what spring rate I needed, would asked Andreani and get back with me.
 
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