Rear Ride Height

Wheels, shocks, forks, frame
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rc46
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Rear Ride Height

Post by rc46 »

Can someone do me a favour?

If you have a standard KR1-s With Standard Shock in good nick, Can you take a measurement for me? From the center of your rear axel Straight up to the bottom of the sub frame?

In my quest to find out if the R6 shock is causing problems I want to know what a standard bike's ride height is and take it from there.
I have a feeling the Extra inch up from what i had before with Tie Rods is causing my front to be pushed to hard...

But im gona check every avenue first,

Thanks
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the-elf
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Post by the-elf »

Jamie,

I could never get any good feel out of the standard forks. They judder and no matter what I did to them it never went away. Your best bet is to swap them for a decent cartridge type of fork. Evil Bay time me thinks :D
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rc46
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Post by rc46 »

Aye, I am looking But i dont want to buy something and get the same problem, Before i swapped over the bike was tracking well, and feedback was good, Only got the judder when i pushed hard round the out side of 1098's :o :D :D

Now (well i only did 1 sess at cadwell) the judder is comming on allot quicker, Now this could be because the forks are shite and the Rear shock is now working, OR its just pushing to hard..

If i can fix it Or at least improve it, ill know that the r6 shock id the right way to go...

All about testing, Hopefully this will also help other's who are thinking about the conversion.

Deep down I think im flogging a dead Horse as the forks are Basic but worth a try to start with!

Whats your ride height NOW outa intrest and do you have the same rake and height at the front before you swapped front ends?
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the-elf
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Post by the-elf »

My front end has the same height as standard but the rear is raised a lot so the rake is shorter than normal, she slaps like a drunken bitch on a saturday night but turns in really quick and loads the front so it grips like shit on a blanket. It really suits my riding style as I do like to push the front hard. The standard forks are crap and if your finding the limit now it'll only get worse the harder you ride.

Swap them for something half decent. You may need to re-spring the new forks but you can't tell that until you've fitted them and set up the sag. What type you go for will depend on if you want USD one's or not, just make sure they are fully adjustable. If I was doing it now I'll look at some of the later ZX6R type with radial calipers etc but then I am a poser :lol: :lol: .

Then again I am happy with the ZXR 400 SP one's I've got fitted now and as they cost over a grand to have the one off ohlins internals made and fitted I don't plan on ever changing them.
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JanBros
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Post by JanBros »

standard forks ain't crap.

keep them in good condition, and they do what they have to do.

if they were crap, I'm sure Mark J would have switched them to :wink:
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rc46
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Post by rc46 »

:lol: :lol: fight fight Fight, I wouldnt mess Elf he has Green Hair LOL

Spoke to Maxton Today, they rekon the oil could have caused it to become over Dampened so it wouldnt move as well under load!, hence they feel much better with the new Oil, Also given me the Air Gap wich isnt far off standard at 140mm,

So ill set that up Friday and with pending MOT next week have a blast to see if it is the rear R6 shock just making the bike run Funny with to much ride height!

Still would like that measurement if anyone can get it, just need two easy referance points One on the Swinger one on the sub frame and the distance between them, Rear spindle to say the back of the Ali hanger weld on the sub frame!
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the-elf
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Post by the-elf »

rc46 wrote::lol: :lol: fight fight Fight, I wouldnt mess Elf he has Green Hair LOL
Thank god for that I was thinking it was going white :lol: :lol:
Spoke to Maxton Today, they rekon the oil could have caused it to become over Dampened so it wouldnt move as well under load!, hence they feel much better with the new Oil, Also given me the Air Gap wich isnt far off standard at 140mm,
Well as your forks are modified Maxton forks you won't get any better without swapping them for something more modern. Lets hope they are working better now.

MJ was on about swapping his for TZ or was it TZR SP forks when he gets some spare time :D and his KR one's have been well reworked internally.
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rc46
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Post by rc46 »

RIGHT!!!

For those of you who are thinking about a R6 shock,,, Fitting it is the easy Bit!

I have found a few things out.

With a Standard rear wheel and standard tie rods I really think the R6 shock is going to push your front end ALLOT so make sure your front forks are up to it. This is especially if its for a road bike, I would go as far to recomend that you raies the front that 10mm (standard setting on KR-1S) to help componsate a little but try it fist and see how you go!

With a 17" rear wheel you are still gona be pushing the front hard but obviously not as much. as over all is abot 10mm less from the ground!

With Big thanks to Charles for taking the Measurement for me i have found out that the R6 rear shock gives you approx 40mm of extra ride height, Thats allot. :!: It also has a few problems in that your chain will now rub against your standard chambers (assuming your running a 15/45 set up) the chain will clear when you sit on the bike but will touch from time to time while your riding as the shock moves.

I have a 14/42 in at the momment and it still touch's but not as bad.

As an exchange shock I still think its worth it, But dont expect just to slap it in and ride away. I also had to up the Preload and dampping on it, but thats cause im fat!!! LOL

Ill give the bike a good run soon and give you some final thoughts, But now the front has been redone the little runs round the block feel MUCH better so looking forward to that thrash!

On a side note i think i have found the problem with my front end, After speaking to MAXTON, i found that the previous owner must have topped the oil up or didnt speak to maxton when doing the change. The forks look like they stopped working under HARD load as there wasnt enough air in there. previous oil was 420ml I now have 385ml with an airgap of 140mm ( the forks are Maxton tunned so will differ to the standard ones)
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the-elf
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Post by the-elf »

I had the same problem with the chain rubbing the chambers with no weight on the bike. I got a blow torch out and heated the bottom brackets up and bent them slightly to give a bit move clearance.

Glad you've got the forks working better.
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Post by mgtkr1 »

the d forks were terrible from day one, according too the mags at thew time so if they werte bad then, they'll be utter shite now. maxton can turn the forks in to some thing almost decent tho and im sure it can be done to a certain extent by swapping oils/springs and generally looking after them. in a nutshell the maxton forks (std reworked kr1 s) a probably quite good but working with a (lets face it, 18 yrs newer therefore bloody good) r6 shock will show the weaknesses of the forks quite dramaticly. i think the std forks can be made to work fairly well, the problem is theres no scope for track/road side improvement. in std form they are rubbish unless the tarmac is billiard smooth and you weigh 18st!!
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Post by scooble »

I have just done the R6 shock conversion and also changed back to the original tie rods, I also have a 17" rear wheel, but also have ZXR400 forks. Consequently, I haven't a clue how its going to handle. :-k

If the R6 shock mod raises the rear by 40mm on an 18", that should mean by fitting a 17" should raise it by 28mm. (40-12).
I think the ZXR400 forks are 10mm longer than KR1S forks, which in theory should offset the rear ride height by 10mm giving (40-12-10=18mm), furthermore, the KR1S forks are normally dropped by 10mm in the yokes, so if I raise my forks so that they are flush with the top yoke, this in theory would give me (40-12-10-10=8mm).

this would mean an effective rise in rear ride height by 8mm but also increase the ground clearance and C of G and increase the moment around the contact patch on the front wheel.

Is this right?
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rc46
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Post by rc46 »

MMMM, Scooble take some measurements today, that 40mm increase was from spindle only not the floor so i guess the wheel wasnt taken into the sum's, Errr i guess the bike will be lower at the back anyway so the theroy sounds right.

Ill measure up today,

go from below spindle on the floor, using the spindle as a guide go straight up to the sub frame, ill do the same and get back here later, ill post up the standard height as well based on what charles gave me!
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Post by the-elf »

scooble wrote:I have just done the R6 shock conversion and also changed back to the original tie rods, I also have a 17" rear wheel, but also have ZXR400 forks. Consequently, I haven't a clue how its going to handle. :-k
I've got a simular setup but with SP forks and an Ohlins rear shock which is about the same length as the R6 shock and an RGV swing arm like yours. My front forks have 20mm showing above the yokes. and I have jacked the rear up. I just measured mine and from the rear wheel spindle to the point where the bottom rail for the rear foot rest rejoins the subframe is 550mm. This handles well for the track but is probably a too high for road use as there is too much weight onto the front. Instead of using KR1s tiebars I made some spacers and made some simular to the RGV ones but 12mm longer.

This setup is a tad extreme so I'll probably make some new tiebars about 16mm longer then the RGV one's to lower the rear a tad more as I have found that it has a tad too much weight on the front in the wet.

I would guess at about 500mm for a good general setting the idea is to try to set up the front and rear ride height so the weight at the front and rear is balanced 50%-50% (thats the theory anyway :D ), You'll need two bathroom scales to do this. Once thats done, just setup the sag.
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