[zukenutter]

I've been giving that pic of monleys a bit of thought and wondering if those coils are his original 80+ Bull Bar load coils, may explain them not wanting to compress properly.

[Gwagensteve]

I've been doing a bit of searching to find out why coil bind is bad, and I can't really find anything specific except everyone says it's bad for the reasons I've outlined before.

In fact, I found a page on spring testing from a motorsport site where coil bind is considered "destructive testing" and the coil is immediately thrown away if it's been bound even once.

The consensus is that coil bind leads to premature fatigue and poor handling.

The only exception is that it seems some US circle track racers (stock cars) use coil bind on the outside wheel - (they're only turning left remember) along with very high antiroll bar rates to almost completely eliminate body roll. I don't think that's a relevant example for our application.

Also bear in mind that suzuki designed the bumpstop of the car as part of the suspension - bumpstops have a "rate" just like a spring. A bound coil has infinite "rate" as it's impossible to compress any further. I would agree if a car was running limited compression travel before bind it might have very terrible road handling as the spring rate would go from low (say 149lb/") to infinite in a very small amount of travel. This will/might result in roll oversteer, which is quite nasty. It's a common problem with lowered MX5's apparently.

To (slightly) complicate things, it's clear that with very severe misalignment, like that in Monley's photo, the spring might compress further than its normal "bind" point because the coils can effectively overlap due to the misalignment.

Has anyone noticed their 80mm springs "settling" after installation, or difficulty with the holding height?

*Hmmm... thinks*

I know Monley is running 40mm spacers, apparently to "restore" 80mm of lift due to his bar and winch? (is that the case?)

Lets assume the bar and winch weigh 100KG (and I reckon it would be nowhere near that) and stock 80mm springs have a rate of 160lb/"

100KG=220lb, or 110lb per side.

110/160= 0.68, or 17.5mm. That's about what you'd expect from a bar and winch install. If it's taken 40mm to "correct" that much weight, then the springs are flogged, and that might well be due to them being repeatedly bound.

In reality, I'd say 80mm springs have well over 160lb/" rate and the bar/winch weighs somewhat less than 100Kg, but that only makes the situation worse.

Steve.

[monley]

They are winch load coils. I will do a bit if a write up tonight of the stages I have been through with my suspension.

[gjb977]

I have the 80mm toughdog springs and shocks. Had them for quite a while. No sway bar either. Haven't had any issues (yet), but then I don't bounce over anything...speed doesn't work in the areas where I live. You need to crawl - easy to get *hung up* on the diffs areas. All tracks are windy, severely rutted and either lantana or scrub right up to the sides of the track.

[BertZook]

Gwagensteve wrote:

I know Monley is running 40mm spacers, apparently to "restore" 80mm of lift due to his bar and winch? (is that the case?)

IMO if u have t use 40mm spacer to level the car then u have a wrong spring for the job and u should be better change it.... so for a"80mm" lift u need to use a 40mm spacer to bring it back to "normal".... ull be better off getting a 45mm or 50mm spring plus ur spacer to achieve the same height

monley wrote:

They are winch load coils. I will do a bit if a write up tonight of the stages I have been through with my suspension.

so saying that and reading this monley post of the spring being rated as "winch bullbar rate" just makes me wonder the issue is not on the front is on the back of the car

so front is not "sagged" is just the back is lifted higher, reason being (I assume) as having a heavier spring rate (lift the car more) its just for taking heavier loads in the back of the car, and as prob monley doesnt carry much load (if any) the spring doesnt settle as they supposed to. So end result is the crappy heavy ride on street that msot ppl complain in TD (that I remember read in here), plus the rear end of the car is getting higher, witch lead u to think "oh the front is sagged" and to you put the spacer on the front to try "to compensate"

I dont have any idea on how the ppl from TD make the calculations and design for their coils, but the reason for this could be as the majority of 4wds are bigger (or huge lol) and most of them have a heavy rear end, plus lots of them need to carry heavy loads in the back.... problem is that in a jimny u never do that... u dnt have the space lol, so they might use a common calculation or % according to the car assuming the jimny would take a certaing amount of load in the back that most of us (if any, for a day to day basis) would do.......... this is just a theory, might be true or not

so instead to fix it with a spacer on the front, I think Monley u should get a smaller coil on the back, get the 60mm TD get rid of the spacer and it should be all nice and level


also if u can try to find a stock jimny and measure his front against yours (if u havent done it yet) to see in reality how much ur front coil has "sagged" if any from the "80mm" lift they supposed to have

[smiffkid]

u bag the tough dog coils because they bind not allowing the diff to hit the front bump stops, this is true
im running factory coils with tough dog 80mm shocks and can only just touch the front bumpstop when completely flexed
the factory springs are at binding point pretty much
so there for any bigger spring will be an issue

in my other jimny that runs 80mm tough dog coils aswell as coil spacers (due to the fact its carry an added 500kgs, yea thats a fuckin heap) it hits the rear bump stops with at least 50 mm length left in the shock tho the rear bump stop wont physically compress that much any way,
the front dont hit as there is no way possible for them to

hope that helps clear a few issues here,

[GRPABT1]

You sure the 80mm shocks on the stock springs aren't bottoming out?

[monley]

Ok where to start


Re: winched rated springs

This has always puzzled me as to why the front end always sat very low with the 80mm lift. It sat low in my car, Smiffkids car and a few others. If we look at gjb977's car here


It's sitting pretty close to level, even with the bar. Now look at mine just after i put the lift in

.

The front is very low compared to gjb977, they are winch rated coils. Makes me wonder about TD ability to make 2 coils the same

Re: Spring length

Ok, so here is a stock spring next to a TD winch rated spring with lengths.







So i would say TD is using coil bind to limit up travel.

Re: Shock length

I dropped the spring out of one side, and lowed the car down until it could not go any further with the shock in.

This is how far of the bump it sit's with the shock "topped out"



Now, don't forget these are customs shocks, and have a compressed lenght of 35mm longer than the shocks that come in the kit.







You can see there is about 20-30mm gap between the diff and the bump stop. If you were running the supplied shocks that come in the 80mm TD kit, they would not topped out (maybe with a big jump they would).



As you can see in this pic, the 31's is tucked right up, into the guard. There is no way i can turn the wheel there with out the tyre hitting several things.

Re: Coil bind

I'm not sure what was going on in the first pic i posted with the coil spacer in, or how the car was flexed up - but it was pretty messy. With out spacer it is much better (still nothing great tho)
Drivers side

Passenger side


The passenger side seems to be a mess compared to the drivers side - not sure why?

Re: Coil spacer

For my setup ATM the there are more pro's of running a spacer's, then not running them.

With out the spacer in, the coil is un-retained at full droop.





Once again this is not a issue with the stock 80mm lift kit.

Issues when not running them

A) The tyre hit's the front body mount on the chassis at full locke

B) Tyre hit's the head light bucket

C) Coil is not retained (less ground pressure)

D) Coil can fall out

They are only good point's for me because i'm to lazy to sort out those issue. Bump stop spacers and limiting straps would solve 3 out of 4 issues there. Not sure how to get around the tyre hitting the body mount bracket tho

Ok, now onto actual flex gained from a lift kit ( i know this isn't a very accurate comparison cus the car is in a different circumstance in every photo. In fact, almost to many variables to make a accurate judgement, but it's the best i can provide with the pictures i have).

Here's a pic of my car with the "off the self kit " flexed up.





With the spacers and longer front shocks





With stock front's in the rear, pro comp rear shocks, extended rear bump stops.



(that's all the pics i have with that setup i think)

Pics from today with out the spacers






Now here' a pic of smiffkids jimny with stock coils and TD shocks



It seems that the front end is flexing much harder, and is also forcing the rear to work harder. I know they are only pics, and don't have anyway to show the angle of the body compared to the angle of the axle through out the different stages of me playing with my suspension over the last 18months. All you can do is have a look at the visual difference between the pictures

At the end of the day i'm happy with the flex i am getting considering all the mounts are all factory. While my setup still has it's issues and draw backs, they are all things i can live with. Things that will be addressed soon are new arms for the front, and that's it.

The point i'm trying to get across here is, the 80mm TD kit doesn't have as many issues as what Steve has mentioned above. It does however not improve flex all that much

It would be good to see the some pics of the jimny bit's lift in all it's separate component's. I would also like to see pics from Zukenutter's suspension setup's from the last 10years he has had with the jimny to

I think a with a bit more research there is a good setup that could be sold as a "off the self kit" That has good flex, with little draw backs. TD have NOT done that here I think jimny bit's are winning that race....

[alien]

the fact it doesnt increase the flex all that much is one of steve's main points i think... the suspension geometry allows for X amount of movement and thats it... as shown in the pics.

very cool to see all the incarnations of your suspension setups in one spot too =)

[want33s]

EDIT: Added "Jimny" to thread title for searching.

[smiffkid]

When tank ran standard coils and shocks. I could get a wheel no more then 300 mm in the air. With the 80mm bolt on kit I was gettin close on 650 mm so must gain flex when fittin the lift.

[SierraDan]

Or lift.

[Mike57]

I was not able to speak to the ARB engineer yesterday as he is on leave. I have sent him an email so we will see what comes of that. Today one of my mates who is a mechanical (automotive) engineer dropped in to say hello and I asked him for his opinion about using the spring as a bump stop. He also said this is a no-no because of the stress on the mounts and his opinion was that if done repeatedly the spring would fracture and fail. Another opinion to add to the mix.

[zukenutter]

This thread has certainly got me thinking about bump stop extensions, just enough to prevent bind

[atari4x4]

zukenutter wrote:

This thread has certainly got me thinking about bump stop extensions, just enough to prevent bind

I wonoder if you could fit a shourt air bumpstop, inplace of the original ones... look about the same size.

i bumpstopped the shit out of the calmini kit in my Vit all those years ago when it when together as it worked on the principal of using coil bind as a bumpstop. i'm certain it made the ride nicer as it would come to rest on the bumpstop before the harshness of coil bind.

[zukenutter]

drewmouli wrote:

Im thinking of welding a bit of pipe(capped off) onto the spring mount on the diff, so the factory bump stop comes down and hits it.

Will be a biatch to swap/remove coils

[Gwagensteve]

monkey wrote:

The point i'm trying to get across here is, the 80mm TD kit doesn't have as many issues as what Steve has mentioned above. It does however not improve flex all that much

really? I don't think that's clear from your (still helpful) photos at all.

I'm really not trying to a hater, but if the 80mm TD shocks really are only 35mm shorter fully compressed, then I can't see that the stock bumpstops can ever work the way suzuki intended. For safety, you need to allow 1/2 the height of the bumpstop +1 of shock shaft showing from the point the axle reaches the bumpstop.

I can't see if the coils will bind in the photos you've taken, mostly because you have a long shock in there that's preventing binding.

You would need to retake those photos with the shock pulled to see if the coils bound. However, the normal sign of a binding coil is no paint where they touch, and your paint is fine. I don't know how long you ran the 80mm coils with "stock" TD 80mm shocks, (?) but maybe they are long enough to prevent bind too?

As for spacing bumpstops, do the Jimny stops unthread? if so, making spacers is pretty easy. I've welded mine in, but that's an alignment issue ( like on the rear of a Vitara) I wouldn't have thought you'd be swapping springs enough for the added wrangling to get past a spacer to be a bit problem.

as for a "low front" How was that measured? was the back coming up 80mm and the front less? Most aftermarket suspension makers build a bit more height into the rear assuming the car will carry some load. Load on the front end changes little with payload so it's much easier to design to hold a set height. The #1 thing the buyer of a kit will complain of is "less than the advertised height" so they will normally aim over, especially for the rear.

I'm also not surprised that the front is lower with the "winch" springs. Why? Because as they add rate the spring designer is going to have to design a shorter spring or else the car will be way too high or too soft in rate. They also don't know which winch and which bar you have. Someone's 60KG bar and winch might be someone else's 90kg, so designing a short, stiff spring will guarantee height with a range of different combinations without having the car go too high with a light combination.

It's all a compromise on top of an already, very compromised package. I'm not being a Jimny hater - it's a by-product of a car designed to be low and with short, suspension travel, no different than a leaf sierra.

Steve.

[zooky08]

jimny bits coils and a bar and winch in my jimny sat level when i put the 75mm kit in. jimny bits front coils aint even bullbar or winch springs
jb front coils are longer then the rears as well. also a few people say the 75mm lift is actually more higher then they say, havnt measured my springs so i have no proof on this

[monley]

Gwagensteve wrote:

monkey wrote:

The point i'm trying to get across here is, the 80mm TD kit doesn't have as many issues as what Steve has mentioned above. It does however not improve flex all that much

really? I don't think that's clear from your (still helpful) photos at all.


Steve.

Sorry, i was not really with it when i wrote that up last night - I meant it does have the issues you mentioned

But, as you also said, there is no evidence of coil bind. If the car is flexed on something like this



It still won't reach full compression (shock will still have 20-30mm before it will bottom out). Maybe the coil isn't binding, but instead the increased coil rate is stopping the diff from reaching full compression so there isn't coil bind? Just a bit of a crazy thought, cus if i was to go stand on the drivers side there, the car would lay over to the drivers side another 30mm or so - coil spacer or not

[smiffkid]

The only way to test coil bind is with a slow motion camera while either jumping the car with enough force to comPress the coil or hittin things fast
Flex won't cause the same strain as a high speed hit.

[SierraDan]

In a jimny specifically? or as a general statement. because i'd beg to differ if so.

[smiffkid]

Well most vehicles. The coil
Compresses More when hitting something fast, ie when u crawling u don't have the se
Force. Unless u have big bumPstops to stop them from binding all together

[Gwagensteve]

smiffkid wrote:

Well most vehicles. The coil
Compresses More when hitting something fast, ie when u crawling u don't have the se
Force. Unless u have big bumPstops to stop them from binding all together

Most vehicles don't bind coils so it is a moot point. If there is any risk of coils binding then the bumpstops are too short. It's also the reason that bumpstops need to be spaced by the height of any coil spacer fitted.

Steve

[SierraDan]

smiffkid wrote:

Well most vehicles. The coil
Compresses More when hitting something fast, ie when u crawling u don't have the se
Force. Unless u have big bumPstops to stop them from binding all together

My mates rodeo had very soft coils in the rear that bound up when crawling.
It's coil/car dependent on whether it will happen or not.

[Gwagensteve]

Yes but that's a custom setup (yes?)

Steve

[SierraDan]

Gwagensteve wrote:

Yes but that's a custom setup (yes?)

Steve

Yeah, but its a pretty general statement by smiffkid. If you put a certain coil in the jimny it would bind at ride height.

I'm just reinforcing that the coils designed for jimny's arent the right ones as they're designed with other things as a compromise.

[zooky08]

okay not here to argue or debate about the two kits, any way took some pics of the jimny bits kit.
i didnt go as far as monley as i really couldnt be bothered to do the same thing as he did.
ill try post some picture, im no good at explaining how the suspension works and all that, so pics are 1000 words

the jimny bits 75mm lift isnt much better the the 80mm td kit, still a shit load away from the bumper stops, i reckon my coils are starting to bind in these pics.
so bumper stops are on the cards now

so heres the pics, this is the front pretty much at full droop and i think the other side front coil is starting to bind


so heres the pic of the coil and if you look closely u can see its a fair way from the bumper stops. will never get to the stock bumper stops.


this is the rear flex, i can get two more inches droop in the rear if i take the shocks out. the procomp es1000 i bought to suit the kit actually to short they top out so adding shock relocator mounts ill get my full droop that the shocks dont aloud. if i add the shock relocators there is still enough shock shaft there so it doesnt bottom out. will also need very big bumper stops



and just a pic of the castor correction arms flexing with td bushes


so started to design my bumperstops now before i really do some damage to my shocks and coils

[SierraDan]

So back to Jimny's...

Is it looking like the way to go is to reduce the amount of loops in the coil?

[monley]

SierraDan wrote:

So back to Jimny's...

Is it looking like the way to go is to reduce the amount of loops in the coil?

Yes, but to maintain the same height you would need to increase the coil rate, which will make it harder to compressor the suspension.

[smiffkid]

the photo of the rear at full flex
the bump stop isnt inside the coil its the little pointy object between the wheel and the chassis
not very visable in said photo

can any body show me a picture of any coil lift that actually hits front bump stops
i know the tough dog 80mm coils do in the rear but can any 1 show a picture beside my car with stock coils of them hitin front bump stops

if so then ill be suprised and proberly buy said coils when i change my suspension next