F4i shock conversion?
- Thread starter GeorgiK
- Start date
I highly doubt it has the same bottom clevis since the Fz6r bottom clevis is very wide. The clevises need to be the same width, use the same size bolts and the shocks should be roughly the same length eye to eye for it to be a true "drop in". If you can get your hands on one for measurements, I have a stock Fz6r shock on the shelf I can measure for you
I forget how it went when I used a gsxr600 shock on my Ninja 300 but I think 5mm of shock length equated to an inch of actual ride height higher or lower (on the Ninja at least).
Also, keep in mind that ypu would need to calculate the correct spring rate going by what you need for the Fz6r. Different bikes need different spring rates (for different weight riders) depending on the linkage ratio of the bike. Does that make sense? That is how it was explained to me by Dan at Traxxion Dynamics.
Also, keep in mind that ypu would need to calculate the correct spring rate going by what you need for the Fz6r. Different bikes need different spring rates (for different weight riders) depending on the linkage ratio of the bike. Does that make sense? That is how it was explained to me by Dan at Traxxion Dynamics.
I've looked more into this and the shock from the f4i can be put on the fz6r but it isn't really worth it, for the fz6 it is easier to make it fit the video I mentioned from Dave Moss had an fz6r shown but the advice was for the fz6 with the regular shock.
The shock from the CBR 600rr (2007+) is a good fit considering length and spring rate, I'll look more into this when I will go ride with some friends with a 600rr and take some measures to see if the piggyback reservoir can fit.
Also, if the reservoir has space when the shock is fully extended, it won't hit anything as it compresses? And what type of spacers are recommended, at the shock mounts there are a bearing with a bushing, and considering that most shocks don't have the mounts as wide as those on the fz6r wouldn't the bearing make contact with outside elements like water and dust and should I be concerned about spacers rub against the mounts and the shock or impeding the movement of the shock in any way?
The shock from the CBR 600rr (2007+) is a good fit considering length and spring rate, I'll look more into this when I will go ride with some friends with a 600rr and take some measures to see if the piggyback reservoir can fit.
Also, if the reservoir has space when the shock is fully extended, it won't hit anything as it compresses? And what type of spacers are recommended, at the shock mounts there are a bearing with a bushing, and considering that most shocks don't have the mounts as wide as those on the fz6r wouldn't the bearing make contact with outside elements like water and dust and should I be concerned about spacers rub against the mounts and the shock or impeding the movement of the shock in any way?
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Not sure how dead set you are on an external reservoir shock, but the stock R3 rear shock fits like stock if you pop in the lower spacers from the FZ6R. They have a 16.4 kg/mm spring rate and are like $30 shipped on eBay. I have a bunch of pictures and stuff in my build thread on here.
You'll have to rely on trial and error for figuring out fitment unfortunately. Not really any good way to figure out if it'll interfere with anything without just trying to shove it in there.
The stock 07+ CBR shock mounts look like they have seals and should be fine against water and dust. The spacers would just need to match the size of that small center section of the shock mounts. Could use aluminum or steel.
I just want a fully adjustable shock to have a working rear suspension and not have change shocks because they lost some of their properties with age and wear, and spend max $150. And because of that those shocks are some of the options I could try.
The R3 shock if it's $30 then it's a steal, despite the fact I consider it disposable but where I live I don't think I will be able to find it at such prices and from ebay the shipping is expensive. Asking for the case I manage to find a low mileage one for a reasonable price, how did the bike change?
I'll ask the vendor online for actual eye-to-eye measurements, and other measurements like the one in the picture with the f4i shock to know if it is worthwhile adapting for the fz6r before I buy one. From what I've seen online it would be a good option
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Okay, so here are some recent findings
I do not know the exact angle of how the shock is mounted but seems anywhere between 30 and 45 degrees. ( If you can and know how to measure it please do)
The rear center stand makes the suspension extend at its max and there is about 20mm gap between the center of tire and the road ( measured it on uneven terrain, I don't know exactly the gap number /tire wear could influence this gap overtime )
So considering those 2 and a formula I found on the internet
"The formula for the change in ride height (Δh) is:
Δh=ΔL×cos(θ)\Delta h = \Delta L \times \cos(\theta)Δh=ΔL×cos(θ)" ( difference in length multiplied by the angle of the shock, works for suspension without linkages)
I'd say that a 15mm raise in the rear would be safe for the center stand to work at all times
If the shock is mounted at 30 degrees we can fit a 18mm longer shock max/ for 45 degrees we can do a 21mm longer one so I'd say a 295mm eye-to-eye is a maximum safe number.
Also, if someone wants to mount whatever model shock they want you need those types with the bearing at both mounts, not the ones with a bearing at the top mount and a bracket at the lower mount)
A guy with a cbr600rr was outside when I was out riding and I got to measure the shock, but he had the one with the separate reservoir
Lenght it says online 293 eye to eye so it is fine
1' top mount
1.6' bottom mount
The hose for the reservoir needs to be 60mm at least to have where to actually mount the reservoir to the frame, excluding extra space and it was much longer than needed.
His bike had 40k km and the shock was still 1000 times better than what I currently have.
I'll wait a bit longer to see if any person with a 600rr with the piggyback reservoir PC40 shows up.
Here are other shock models worth a look ( based on length and mounts/ not on suspension performance, except adjustability):
I have no clue about model years
-R3 stock shock: low price for a new-ish one, idk about how it rides on the FZ6R
-R3 upgrade shock: lower price compared to fz6r upgrade shock idk, I didn't look into this one option yet
-CBR 900/929/954RR shocks: fully adjustable, 285/286mm eye to eye, I don't know if the piggyback reservoir has enough space, old and a bit more expensive
-CBR 600RR Pc40 shock: stay tuned for updates
-Ninja 650 shock: this one (and the r3 shock) are actually designed to be mounted on bikes without linkages so it should perform nicely, 290mm
-Ninja 650 upgrade shock: probably best out of all these options
-Fz6R/XJ6 upgrade shock: self-explanatory
-F4I shock: Good option but requires a lowering linkage and precise calculations for the ride height to turn out well, 305mm or longer e-t-e
Also, I learned that the spring rate should be a lot higher than what I thought earlier (for the type of riding I do) because of the absence of a linkage system and progressive springs on shocks, about 19.xx kg/mm.
For now, I hope I'll get a chance to measure the piggyback reservoir on the 600rr and see if it has space to clear.
If it clears, I'll get that since a PC40 with piggyback, and low/lower mileage is like $60 with shipping where I live.
It is not perfect, but it has a slightly stiffer spring and damping adjustability and I'm okay with that
If you guys want to put any time and effort into this more, I listed some options there, spring rate information about those would be greatly appreciated. I won't look into this more, for now.
I do not know the exact angle of how the shock is mounted but seems anywhere between 30 and 45 degrees. ( If you can and know how to measure it please do)
The rear center stand makes the suspension extend at its max and there is about 20mm gap between the center of tire and the road ( measured it on uneven terrain, I don't know exactly the gap number /tire wear could influence this gap overtime )
So considering those 2 and a formula I found on the internet
"The formula for the change in ride height (Δh) is:
Δh=ΔL×cos(θ)\Delta h = \Delta L \times \cos(\theta)Δh=ΔL×cos(θ)" ( difference in length multiplied by the angle of the shock, works for suspension without linkages)
I'd say that a 15mm raise in the rear would be safe for the center stand to work at all times
If the shock is mounted at 30 degrees we can fit a 18mm longer shock max/ for 45 degrees we can do a 21mm longer one so I'd say a 295mm eye-to-eye is a maximum safe number.
Also, if someone wants to mount whatever model shock they want you need those types with the bearing at both mounts, not the ones with a bearing at the top mount and a bracket at the lower mount)
A guy with a cbr600rr was outside when I was out riding and I got to measure the shock, but he had the one with the separate reservoir
Lenght it says online 293 eye to eye so it is fine
1' top mount
1.6' bottom mount
The hose for the reservoir needs to be 60mm at least to have where to actually mount the reservoir to the frame, excluding extra space and it was much longer than needed.
His bike had 40k km and the shock was still 1000 times better than what I currently have.
I'll wait a bit longer to see if any person with a 600rr with the piggyback reservoir PC40 shows up.
Here are other shock models worth a look ( based on length and mounts/ not on suspension performance, except adjustability):
I have no clue about model years
-R3 stock shock: low price for a new-ish one, idk about how it rides on the FZ6R
-R3 upgrade shock: lower price compared to fz6r upgrade shock idk, I didn't look into this one option yet
-CBR 900/929/954RR shocks: fully adjustable, 285/286mm eye to eye, I don't know if the piggyback reservoir has enough space, old and a bit more expensive
-CBR 600RR Pc40 shock: stay tuned for updates
-Ninja 650 shock: this one (and the r3 shock) are actually designed to be mounted on bikes without linkages so it should perform nicely, 290mm
-Ninja 650 upgrade shock: probably best out of all these options
-Fz6R/XJ6 upgrade shock: self-explanatory
-F4I shock: Good option but requires a lowering linkage and precise calculations for the ride height to turn out well, 305mm or longer e-t-e
Also, I learned that the spring rate should be a lot higher than what I thought earlier (for the type of riding I do) because of the absence of a linkage system and progressive springs on shocks, about 19.xx kg/mm.
For now, I hope I'll get a chance to measure the piggyback reservoir on the 600rr and see if it has space to clear.
If it clears, I'll get that since a PC40 with piggyback, and low/lower mileage is like $60 with shipping where I live.
It is not perfect, but it has a slightly stiffer spring and damping adjustability and I'm okay with that
If you guys want to put any time and effort into this more, I listed some options there, spring rate information about those would be greatly appreciated. I won't look into this more, for now.
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RaceTech's site has a spring rate search and most of the time has all the stock info when you input the bike.
Unfortunately I haven't gotten a chance to ride it yet. I'm still finishing up repairs from a crash last year. I might be able to report back this weekend though.
The shock design between the R3 and FZ6R is essentially the same and there's no ride height change so I'm not really expecting much change aside from a firmer ride. For clarity, most of my riding is commuting and occasionally enjoying some twisties so I probably won't have much input on how it behaves with more aggressive riding. I mainly just wanted to stiffen up the rear a bit because the stock shock is way too compliant. My recommended rear rate is also 19.xx kg/mm, but I didn't feel like spending an arm and a leg so the 16.4 kg/mm from the R3 was perfect for the price and my use case.