- Thread starter PhillipM
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dobbslc
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Hell that Rangie seems to be catching you up!
Put your foot down man!
Love this thread, it's great seeing the buggy getting faster and how you work out the niggles as you go along.
As you mentioned earlier it's great when other competitors sneak over to have a look at what's just thrashed them
Put your foot down man!
Love this thread, it's great seeing the buggy getting faster and how you work out the niggles as you go along.
As you mentioned earlier it's great when other competitors sneak over to have a look at what's just thrashed them
Bullet2012
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Discovery
PhillipM
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Those Disco's are fast!
Well not that one. But some are
Yea it's nice to have people over talking through what we did with parts and stuff, keeps things interesting, unfortunately a lot of the sport has gone away from homebrew cars to bought in things and bolt on kits so it's a bit different still.
Well not that one. But some are
Yea it's nice to have people over talking through what we did with parts and stuff, keeps things interesting, unfortunately a lot of the sport has gone away from homebrew cars to bought in things and bolt on kits so it's a bit different still.
stuvy
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Mine isThose Disco's are fast!
Well not that one. But some are
Yea it's nice to have people over talking through what we did with parts and stuff, keeps things interesting, unfortunately a lot of the sport has gone away from homebrew cars to bought in things and bolt on kits so it's a bit different still.
PhillipM
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So Stuvy, when you racing yours?
Front end plan decided - just gonna make the whole beam and arms on the bench, fit the new uprights to it and cut one off and the other on - that's because it lets us just use those arms as spares, put the castor in the beam instead of the arms where it should have been to start with, and also go up slightly on the beam diameter to allow larger bushes with push in split bearing bushes - makes things more accurate and cheaper to replace when they wear then.
It's a little more work but also makes it easy to jig and make off the car on the bench instead.
Front end plan decided - just gonna make the whole beam and arms on the bench, fit the new uprights to it and cut one off and the other on - that's because it lets us just use those arms as spares, put the castor in the beam instead of the arms where it should have been to start with, and also go up slightly on the beam diameter to allow larger bushes with push in split bearing bushes - makes things more accurate and cheaper to replace when they wear then.
It's a little more work but also makes it easy to jig and make off the car on the bench instead.
stuvy
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Story of my life helping others out all the timeThat's our problem atm, got a friends car in the back for the last 2 months so the poor buggy got it's upgrades delayed
I do have a great core group of mates that return the favour but would be nice to turn assets into cash in the bank
PhillipM
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Right, didn't have time to fit the new uprights so 2 sets of new front arms made instead to tide us over for a while - they've got a reinforcement around the weld area's to prevent cracking starting there now - but the pivots are still the same where they bent so they don't bend the beam still if they take a big impact:
The front 15mm arb had bent in the hit so it's had to go back on an 18mm one as it's the only spare I have for now, so we're probably pushing a bit more mid-corner understeer, so to counter that I've shimmed out the rear hubs between them and the arms, so it's got an extra 2mm of rear toe out. Might make it too squirrelly now but we'll find out!
Also revalved the rear dampers as they didn't have anywhere near enough midrange damping and we were nearly out of adjustment range:
And finally have the new seats in, one year later:
These were the reason the front suspension didn't get done. They looked like they'd fit in with a little work. They didn't.
one, they have a little more lean angle on than the old seats, that's a good thing for stopping your ass getting sore while bouncing along rough terrain, because it spreads the load more over your thighs and back - and they also have wider shoulders and some side impact padding for the helmets, also a good thing if your head is bouncing around, but... that's a bad thing if you're trying to fit it in a tiny cabin that was basically built around some smaller framed Corbeau's.
So the seat bases needed moving forwards, quite a bit, and the seats are a bit taller as they have a few inches more padding in the base and they're a stronger/safer seat overall, which means tilting them and shuffling forwards a little more just to make sure there's plenty of roof clearance.
By this point, your knees are on the dashboard, or your feet are through the bulkhead, and as I quite like my feet and really don't fancy extreme weight saving measures like taking my legs off below the kneecaps, some drastic surgery to the car comes in....
Firstly, the co-drivers footrest (and windscreen washer tank), gets pushed forwards and now becomes part of the bulkhead itself:
Along with modifications to the bulkhead and pushing forwards the battery tray too.
And then the next trick is the drivers side, now here the pedals were right up against the bulkhead anyway, pushing them forward then required cutting and folding a few bulkhead that is a few inches further back, pushing the fuel tank and brake reservoirs forwards slightly so the hoses all reach the master cylinders - which are also getting pushed forwards a few inches (along with the pedals themselves) on an adaptor plate:
Continuing on with "PhillipM's First Law of Exponentially Cascading Knock On Effects From Changing One Simple Thing", that also then meant remounting the foot rest plate further forwards, and then the throttle cable was no longer long enough so that had to have an extender made for it too, along with remounting the brake sensor switch. Fun times. And the seats aren't in yet.
Onto the next bit - remember I just mentioned about the seats being taller backed and the base foam being thicker? Both great things, but with a caveat. That means the seats need to be lower, as it's a short cab and your head would be far too close to hitting a rollbar tube otherwise.
And because we've just pushed the seats forwards, they hit that diagonal T45 tube we put under the old seats a year or two ago to give some rock protection...so angle grinder back out, and cut out that bar, lower the seats as far possible while still leaving a touch of clearance under them to the floor armour just in case...and then we had to forgo the nice diagonal protection tube (which also stiffened the floorpan) and pop two tubes at angles as close as we could to the seat bases instead, front and back.
Now this might seem a little silly but we've landed on big 1ft diameter stones and rocks before and twice they've punched a hole clean through the floor armour, so this is a little extra weight for peace of mind/protection.
So now there's bars either side of your bum. Just in case. And some little stiffeners just so we don't loose the chassis stiffness benefits that the old bar gave.
I didn't take a picture but as you might guess from the cover being off in front of the gearbox, the gearlinkage has had to be remade and the gearlever shifted left an inch to clear the wider wings of the new seats too, along with 4 new seat mounting frames being made and the harness clip on points being moved to suit.
Don't believe your brain when it goes "They're not that much bigger, we'll get those in, easy"
So yes, a whole lot of time disappeared just to get comfier. But I think it'll be worth it those Motodrive seats were custom fitted/shaped for us and they're so, so much better to sit in.
The front 15mm arb had bent in the hit so it's had to go back on an 18mm one as it's the only spare I have for now, so we're probably pushing a bit more mid-corner understeer, so to counter that I've shimmed out the rear hubs between them and the arms, so it's got an extra 2mm of rear toe out. Might make it too squirrelly now but we'll find out!
Also revalved the rear dampers as they didn't have anywhere near enough midrange damping and we were nearly out of adjustment range:
And finally have the new seats in, one year later:
These were the reason the front suspension didn't get done. They looked like they'd fit in with a little work. They didn't.
one, they have a little more lean angle on than the old seats, that's a good thing for stopping your ass getting sore while bouncing along rough terrain, because it spreads the load more over your thighs and back - and they also have wider shoulders and some side impact padding for the helmets, also a good thing if your head is bouncing around, but... that's a bad thing if you're trying to fit it in a tiny cabin that was basically built around some smaller framed Corbeau's.
So the seat bases needed moving forwards, quite a bit, and the seats are a bit taller as they have a few inches more padding in the base and they're a stronger/safer seat overall, which means tilting them and shuffling forwards a little more just to make sure there's plenty of roof clearance.
By this point, your knees are on the dashboard, or your feet are through the bulkhead, and as I quite like my feet and really don't fancy extreme weight saving measures like taking my legs off below the kneecaps, some drastic surgery to the car comes in....
Firstly, the co-drivers footrest (and windscreen washer tank), gets pushed forwards and now becomes part of the bulkhead itself:
Along with modifications to the bulkhead and pushing forwards the battery tray too.
And then the next trick is the drivers side, now here the pedals were right up against the bulkhead anyway, pushing them forward then required cutting and folding a few bulkhead that is a few inches further back, pushing the fuel tank and brake reservoirs forwards slightly so the hoses all reach the master cylinders - which are also getting pushed forwards a few inches (along with the pedals themselves) on an adaptor plate:
Continuing on with "PhillipM's First Law of Exponentially Cascading Knock On Effects From Changing One Simple Thing", that also then meant remounting the foot rest plate further forwards, and then the throttle cable was no longer long enough so that had to have an extender made for it too, along with remounting the brake sensor switch. Fun times. And the seats aren't in yet.
Onto the next bit - remember I just mentioned about the seats being taller backed and the base foam being thicker? Both great things, but with a caveat. That means the seats need to be lower, as it's a short cab and your head would be far too close to hitting a rollbar tube otherwise.
And because we've just pushed the seats forwards, they hit that diagonal T45 tube we put under the old seats a year or two ago to give some rock protection...so angle grinder back out, and cut out that bar, lower the seats as far possible while still leaving a touch of clearance under them to the floor armour just in case...and then we had to forgo the nice diagonal protection tube (which also stiffened the floorpan) and pop two tubes at angles as close as we could to the seat bases instead, front and back.
Now this might seem a little silly but we've landed on big 1ft diameter stones and rocks before and twice they've punched a hole clean through the floor armour, so this is a little extra weight for peace of mind/protection.
So now there's bars either side of your bum. Just in case. And some little stiffeners just so we don't loose the chassis stiffness benefits that the old bar gave.
I didn't take a picture but as you might guess from the cover being off in front of the gearbox, the gearlinkage has had to be remade and the gearlever shifted left an inch to clear the wider wings of the new seats too, along with 4 new seat mounting frames being made and the harness clip on points being moved to suit.
Don't believe your brain when it goes "They're not that much bigger, we'll get those in, easy"
So yes, a whole lot of time disappeared just to get comfier. But I think it'll be worth it those Motodrive seats were custom fitted/shaped for us and they're so, so much better to sit in.
PhillipM
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- 3,021
As for the revalving, well that was fun - one of the dampers it turns out didn't have the backup washer the correct way around/torqued enough and caused a little wear - nothing on the important bits but you can see the debris on the ally bearing spacer here:
And it also looks like the bleed shims (the big shims on the left with the cutouts) were oriented wrongly - where you'd assume the tabs line up with the little raised bits on the piston, they were 45* rotated on that damper, which then leads to some odd effects as the initial compression pressure acts on the shim stacks behind those and the bleed shims themselves only start to lift in the high speed area.
Unfortunately, I've never been in these dampers before and Fox never used to run bleed shims (they ran holes in the piston for it instead - finally they've moved to the same system you see on most high end stuff with Ohlins/Penske/Reiger to make it easy to change bleed amounts) - so after spotting that I just assumed it was deliberate to soften initial response, and kept things that way around when I rebuilt it.
It was only when I opened the last damper that had the shims the way around I originally expected - and no wear, I realised I should have assembled those bleed shims as I originally intended!
Anyway just for this race I've put the bleed shims back together the way the initial one was setup, and then I'll turn them around for the next race after re-running some fluid sims - I just simply don't have time to correct it right now, and I wasn't expecting basically brand new dampers to be mis-assembled. Should have trusted my instincts there.
I have made quite a change though, there's much less low speed bleed now so that I don't have to rely on running the adjusters on max (that causes issues with sensitivity and the pressure balance inside the dampers).
The flutter stack is massively reduced on the compression side, which is referring to the small shims backing up the large washers on the bottom in the middle there - basically that makes a 2 stage stack so the low/mid speed damping is reduced a lot and the high speed is very stiff. That's fine for the UTV these were coming off where they need to get it suitable for everyone from comfy road use to people hammering them over dunes, but it's also softening the damping right where a race car like this needs it - jump landings, bottoming out from elevation changes, washboard stuff where it's dug out in the mud, etc.
It's almost the same for the rebound side (the top shims) - they've used a flutter stack to give the rebound adjuster more range and with a soft initial stack and then a stiffer high speed stack they can cope with a wide range of spring rates owners are likely to throw at a UTV, basically running a progressive damping curve but with the option to add a lot of low speed rebound control.
That unfortunately for us with quite a lot of spring preload and weight at the rear means that the damping is reduced right where it's controlling the rear kicking up over rolling jumps, as you can see on some of the jump pictures it lands nose heavy a lot of times if it's a steep take off.
The only way to really tame that was to wind the rebound adjuster to almost full hard (it adjusts the low speed mainly but also the mid speed damping somewhat) - but because that also winds up the low speed damping which is mainly body control and handling related, that would make the car very nervous and skitterish on the brakes or the way into a corner so I couldn't go too far.
Given we also don't need that range of adjustment I've pulled that stack completely and now it runs a more conventional tapered stack that gives slightly digressive rebound damping, that means we have a lot more midrange damping, and I can just use the adjuster for what it was designed for - tailoring the handling responses of the car rather than trying to patch up problems in the main valve stack.
I've left the high-speed damping somewhat similar at the moment just for reference but I suspect I'll end up reducing that somewhat anyway, we have quite a lot of unsprung weight, and our tyres are both quite a lot larger and run lower pressures than an UTV - so I think a softer setup there will benefit us more in terms of getting the tyre back in contact with the road sooner vs the sudden increase in contact patch pressure that might cause.
One for another time
Anyway, after all that rambling they're back together and re-gassed:
I also swapped the oil to some low-friction oil - the stock Fox red oil isn't too bad but it has some really bad issues with stiction I've noticed over the years - especially in dampers this size, not so much of an issue in smaller stuff, whereas the stuff I'm using now has some really fancy additive package to reduce friction and wear at the expense of needing changing a little more often.
...while I'm rambling about dampers I wasn't impressed by the pistons either - they're very low flow so they choke the valving on impacts and they have a lot of sharp edge entries into the ports too. I'll be swapping those out for either some higher flow alternatives when I can get hold of some (Fox sell them for racers in the US), or making a pair.
And it also looks like the bleed shims (the big shims on the left with the cutouts) were oriented wrongly - where you'd assume the tabs line up with the little raised bits on the piston, they were 45* rotated on that damper, which then leads to some odd effects as the initial compression pressure acts on the shim stacks behind those and the bleed shims themselves only start to lift in the high speed area.
Unfortunately, I've never been in these dampers before and Fox never used to run bleed shims (they ran holes in the piston for it instead - finally they've moved to the same system you see on most high end stuff with Ohlins/Penske/Reiger to make it easy to change bleed amounts) - so after spotting that I just assumed it was deliberate to soften initial response, and kept things that way around when I rebuilt it.
It was only when I opened the last damper that had the shims the way around I originally expected - and no wear, I realised I should have assembled those bleed shims as I originally intended!
Anyway just for this race I've put the bleed shims back together the way the initial one was setup, and then I'll turn them around for the next race after re-running some fluid sims - I just simply don't have time to correct it right now, and I wasn't expecting basically brand new dampers to be mis-assembled. Should have trusted my instincts there.
I have made quite a change though, there's much less low speed bleed now so that I don't have to rely on running the adjusters on max (that causes issues with sensitivity and the pressure balance inside the dampers).
The flutter stack is massively reduced on the compression side, which is referring to the small shims backing up the large washers on the bottom in the middle there - basically that makes a 2 stage stack so the low/mid speed damping is reduced a lot and the high speed is very stiff. That's fine for the UTV these were coming off where they need to get it suitable for everyone from comfy road use to people hammering them over dunes, but it's also softening the damping right where a race car like this needs it - jump landings, bottoming out from elevation changes, washboard stuff where it's dug out in the mud, etc.
It's almost the same for the rebound side (the top shims) - they've used a flutter stack to give the rebound adjuster more range and with a soft initial stack and then a stiffer high speed stack they can cope with a wide range of spring rates owners are likely to throw at a UTV, basically running a progressive damping curve but with the option to add a lot of low speed rebound control.
That unfortunately for us with quite a lot of spring preload and weight at the rear means that the damping is reduced right where it's controlling the rear kicking up over rolling jumps, as you can see on some of the jump pictures it lands nose heavy a lot of times if it's a steep take off.
The only way to really tame that was to wind the rebound adjuster to almost full hard (it adjusts the low speed mainly but also the mid speed damping somewhat) - but because that also winds up the low speed damping which is mainly body control and handling related, that would make the car very nervous and skitterish on the brakes or the way into a corner so I couldn't go too far.
Given we also don't need that range of adjustment I've pulled that stack completely and now it runs a more conventional tapered stack that gives slightly digressive rebound damping, that means we have a lot more midrange damping, and I can just use the adjuster for what it was designed for - tailoring the handling responses of the car rather than trying to patch up problems in the main valve stack.
I've left the high-speed damping somewhat similar at the moment just for reference but I suspect I'll end up reducing that somewhat anyway, we have quite a lot of unsprung weight, and our tyres are both quite a lot larger and run lower pressures than an UTV - so I think a softer setup there will benefit us more in terms of getting the tyre back in contact with the road sooner vs the sudden increase in contact patch pressure that might cause.
One for another time
Anyway, after all that rambling they're back together and re-gassed:
I also swapped the oil to some low-friction oil - the stock Fox red oil isn't too bad but it has some really bad issues with stiction I've noticed over the years - especially in dampers this size, not so much of an issue in smaller stuff, whereas the stuff I'm using now has some really fancy additive package to reduce friction and wear at the expense of needing changing a little more often.
...while I'm rambling about dampers I wasn't impressed by the pistons either - they're very low flow so they choke the valving on impacts and they have a lot of sharp edge entries into the ports too. I'll be swapping those out for either some higher flow alternatives when I can get hold of some (Fox sell them for racers in the US), or making a pair.
stuvy
Member
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- 9,304
I wanted to put fox air shocks on my old off-roader but no one knew anything about them at the time over 15 years ago now. I’d still love them, do they eliminate body roll?As for the revalving, well that was fun - one of the dampers it turns out didn't have the backup washer the correct way around/torqued enough and caused a little wear - nothing on the important bits but you can see the debris on the ally bearing spacer here:
And it also looks like the bleed shims (the big shims on the left with the cutouts) were oriented wrongly - where you'd assume the tabs line up with the little raised bits on the piston, they were 45* rotated on that damper, which then leads to some odd effects as the initial compression pressure acts on the shim stacks behind those and the bleed shims themselves only start to lift in the high speed area.
Unfortunately, I've never been in these dampers before and Fox never used to run bleed shims (they ran holes in the piston for it instead - finally they've moved to the same system you see on most high end stuff with Ohlins/Penske/Reiger to make it easy to change bleed amounts) - so after spotting that I just assumed it was deliberate to soften initial response, and kept things that way around when I rebuilt it.
It was only when I opened the last damper that had the shims the way around I originally expected - and no wear, I realised I should have assembled those bleed shims as I originally intended!
Anyway just for this race I've put the bleed shims back together the way the initial one was setup, and then I'll turn them around for the next race after re-running some fluid sims - I just simply don't have time to correct it right now, and I wasn't expecting basically brand new dampers to be mis-assembled. Should have trusted my instincts there.
I have made quite a change though, there's much less low speed bleed now so that I don't have to rely on running the adjusters on max (that causes issues with sensitivity and the pressure balance inside the dampers).
The flutter stack is massively reduced on the compression side, which is referring to the small shims backing up the large washers on the bottom in the middle there - basically that makes a 2 stage stack so the low/mid speed damping is reduced a lot and the high speed is very stiff. That's fine for the UTV these were coming off where they need to get it suitable for everyone from comfy road use to people hammering them over dunes, but it's also softening the damping right where a race car like this needs it - jump landings, bottoming out from elevation changes, washboard stuff where it's dug out in the mud, etc.
It's almost the same for the rebound side (the top shims) - they've used a flutter stack to give the rebound adjuster more range and with a soft initial stack and then a stiffer high speed stack they can cope with a wide range of spring rates owners are likely to throw at a UTV, basically running a progressive damping curve but with the option to add a lot of low speed rebound control.
That unfortunately for us with quite a lot of spring preload and weight at the rear means that the damping is reduced right where it's controlling the rear kicking up over rolling jumps, as you can see on some of the jump pictures it lands nose heavy a lot of times if it's a steep take off.
The only way to really tame that was to wind the rebound adjuster to almost full hard (it adjusts the low speed mainly but also the mid speed damping somewhat) - but because that also winds up the low speed damping which is mainly body control and handling related, that would make the car very nervous and skitterish on the brakes or the way into a corner so I couldn't go too far.
Given we also don't need that range of adjustment I've pulled that stack completely and now it runs a more conventional tapered stack that gives slightly digressive rebound damping, that means we have a lot more midrange damping, and I can just use the adjuster for what it was designed for - tailoring the handling responses of the car rather than trying to patch up problems in the main valve stack.
I've left the high-speed damping somewhat similar at the moment just for reference but I suspect I'll end up reducing that somewhat anyway, we have quite a lot of unsprung weight, and our tyres are both quite a lot larger and run lower pressures than an UTV - so I think a softer setup there will benefit us more in terms of getting the tyre back in contact with the road sooner vs the sudden increase in contact patch pressure that might cause.
One for another time
Anyway, after all that rambling they're back together and re-gassed:
I also swapped the oil to some low-friction oil - the stock Fox red oil isn't too bad but it has some really bad issues with stiction I've noticed over the years - especially in dampers this size, not so much of an issue in smaller stuff, whereas the stuff I'm using now has some really fancy additive package to reduce friction and wear at the expense of needing changing a little more often.
...while I'm rambling about dampers I wasn't impressed by the pistons either - they're very low flow so they choke the valving on impacts and they have a lot of sharp edge entries into the ports too. I'll be swapping those out for either some higher flow alternatives when I can get hold of some (Fox sell them for racers in the US), or making a pair.
I was helping out with my nephew autograssing last yr - someone went in a bit clumsy and sideswiped him, came in with a broken coilover. We had a spare but I couldn’t help having a look inside. The stem itself was hollow, for the adjuster, and threaded. Trouble was there was so little steel because of the thread and drilling, the sideswipe snapped it. I’m not saying this was a fox damper (cos I’m old and have a crap memory), but I wasn’t impressed...As for the revalving, well that was fun - one of the dampers it turns out didn't have the backup washer the correct way around/torqued enough and caused a little wear - nothing on the important bits but you can see the debris on the ally bearing spacer here:
And it also looks like the bleed shims (the big shims on the left with the cutouts) were oriented wrongly - where you'd assume the tabs line up with the little raised bits on the piston, they were 45* rotated on that damper, which then leads to some odd effects as the initial compression pressure acts on the shim stacks behind those and the bleed shims themselves only start to lift in the high speed area.
Unfortunately, I've never been in these dampers before and Fox never used to run bleed shims (they ran holes in the piston for it instead - finally they've moved to the same system you see on most high end stuff with Ohlins/Penske/Reiger to make it easy to change bleed amounts) - so after spotting that I just assumed it was deliberate to soften initial response, and kept things that way around when I rebuilt it.
It was only when I opened the last damper that had the shims the way around I originally expected - and no wear, I realised I should have assembled those bleed shims as I originally intended!
Anyway just for this race I've put the bleed shims back together the way the initial one was setup, and then I'll turn them around for the next race after re-running some fluid sims - I just simply don't have time to correct it right now, and I wasn't expecting basically brand new dampers to be mis-assembled. Should have trusted my instincts there.
I have made quite a change though, there's much less low speed bleed now so that I don't have to rely on running the adjusters on max (that causes issues with sensitivity and the pressure balance inside the dampers).
The flutter stack is massively reduced on the compression side, which is referring to the small shims backing up the large washers on the bottom in the middle there - basically that makes a 2 stage stack so the low/mid speed damping is reduced a lot and the high speed is very stiff. That's fine for the UTV these were coming off where they need to get it suitable for everyone from comfy road use to people hammering them over dunes, but it's also softening the damping right where a race car like this needs it - jump landings, bottoming out from elevation changes, washboard stuff where it's dug out in the mud, etc.
It's almost the same for the rebound side (the top shims) - they've used a flutter stack to give the rebound adjuster more range and with a soft initial stack and then a stiffer high speed stack they can cope with a wide range of spring rates owners are likely to throw at a UTV, basically running a progressive damping curve but with the option to add a lot of low speed rebound control.
That unfortunately for us with quite a lot of spring preload and weight at the rear means that the damping is reduced right where it's controlling the rear kicking up over rolling jumps, as you can see on some of the jump pictures it lands nose heavy a lot of times if it's a steep take off.
The only way to really tame that was to wind the rebound adjuster to almost full hard (it adjusts the low speed mainly but also the mid speed damping somewhat) - but because that also winds up the low speed damping which is mainly body control and handling related, that would make the car very nervous and skitterish on the brakes or the way into a corner so I couldn't go too far.
Given we also don't need that range of adjustment I've pulled that stack completely and now it runs a more conventional tapered stack that gives slightly digressive rebound damping, that means we have a lot more midrange damping, and I can just use the adjuster for what it was designed for - tailoring the handling responses of the car rather than trying to patch up problems in the main valve stack.
I've left the high-speed damping somewhat similar at the moment just for reference but I suspect I'll end up reducing that somewhat anyway, we have quite a lot of unsprung weight, and our tyres are both quite a lot larger and run lower pressures than an UTV - so I think a softer setup there will benefit us more in terms of getting the tyre back in contact with the road sooner vs the sudden increase in contact patch pressure that might cause.
One for another time
Anyway, after all that rambling they're back together and re-gassed:
I also swapped the oil to some low-friction oil - the stock Fox red oil isn't too bad but it has some really bad issues with stiction I've noticed over the years - especially in dampers this size, not so much of an issue in smaller stuff, whereas the stuff I'm using now has some really fancy additive package to reduce friction and wear at the expense of needing changing a little more often.
...while I'm rambling about dampers I wasn't impressed by the pistons either - they're very low flow so they choke the valving on impacts and they have a lot of sharp edge entries into the ports too. I'll be swapping those out for either some higher flow alternatives when I can get hold of some (Fox sell them for racers in the US), or making a pair.
I am impressed you do your own nitro injecting though...
PhillipM
Member
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- 3,021
I've been working on them for a couple of decades tbfh, they're relative simple on the old stuff, the newer stuff is getting fancier and a bit more complex to service though.
Air shocks are just basically extra springs as well as dampers, they going to reduce body roll the same way as adding stiffer springs would. Just a little more tunable and you can make the rate change progressive.
