Mk 2 Suspension ideas

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Mk 2 Suspension ideas

Post by 118118 » 03 May 2008, 20:54

Hi Guys,
After a few trips green laning, a friend of mine suggested joining him at the motocross track at Coventry.

So today was the day. I never ridden on a track before and to start with I was rubbish to say the least.
After a few sessions I was starting to get the hang of it. I answer is the faster you go the easier it is!!!
Any way, with the suspension all set to the max I think the front forks need some new stiffer springs as they were bottoming out big time over most of the jumps. Has anyone done this and how do you know what springs to go for?
Over all my mate was well impressed with the CRM's performance.

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Re: Mk 2 Suspension ideas

Post by knackeredMk1 » 03 May 2008, 22:05

You need to go to a respected suspension tuner. You also need to change the springs and damping at both ends.

E.g. If you only change to a higher rated spring on the shock you will make the rebound damping too weak and make the bike prone to throwing you forwards off big bumps/jumps. It will also give the bike a 'stink bug' look and tend to make the front tuck in when cornering.

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Re: Mk 2 Suspension ideas

Post by fallenmikethebike » 04 May 2008, 07:47

you also need to change the landing technique, its always best to get the power on before landing , that way you don,t get the sack of poo like effect when landing.
When you have have learnt the correct technique its so much easier on you and the bike.
Then you can move on to more advanced skills like trimming the bikes elevation in flight, for those occasions you get it wrong, or want to alter the landing spot .
Looking real good though, keep practising.
good luck
mike
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Re: Mk 2 Suspension ideas

Post by sparky » 04 May 2008, 08:44

just out of curiosity where in coventry is that track??
crm250 mk2 designed by a genius, built by craftsmen, ridden by a plonker

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Re: Mk 2 Suspension ideas

Post by aussieklaus » 04 May 2008, 10:11

I like your pics 118118 :D ,
cant wait to get my bike run and go out in the bush for some practice!
The only time I did a little bit of offroading was with my old XL500! And I guess the CRM will do so much better!

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Re: Mk 2 Suspension ideas

Post by 118118 » 04 May 2008, 11:57

sparky wrote:just out of curiosity where in coventry is that track??
Here you go:

G&P MX Park

Coventry / Ryton - G&P MX Park

Lots of big jumps including Table tops, step downs, doubles, ski jumps, etc May not be suitable for beginners

The tracks owned by UK FMX rider Gary Tayler you can find thetrackjust off the coventry airport roundabout, or M69 left at Roundabout, dont take the first turn to Ryton carry on its on the left under the bridge can't miss it.

Contact: 07775652160

Opening Days/Hours: Wed,thur,Sat,Sun starts @ 10am - 4pm

Facilities: Cafe

The track usually runs sessions Schoolboys then a125 session then 200cc-unlimited

Cost: £25 per rider

Great fun but far harder than it looks! :wink:

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Re: Mk 2 Suspension ideas

Post by 118118 » 04 May 2008, 12:01

knackeredMk1 wrote:You need to go to a respected suspension tuner. You also need to change the springs and damping at both ends.

E.g. If you only change to a higher rated spring on the shock you will make the rebound damping too weak and make the bike prone to throwing you forwards off big bumps/jumps. It will also give the bike a 'stink bug' look and tend to make the front tuck in when cornering.
Thanks Knackered,
I understand that the springs can be changed without to much trouble, but how is the damping altered?
Will the original shock be OK of would i have to go for a different unit? (sound expensive!)

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Re: Mk 2 Suspension ideas

Post by knackeredMk1 » 04 May 2008, 13:02

Damping is controlled by a system of flexible shims and holes which control the speed and amount of oil that flows in different directions according to whether the suspension is expanding or contracting and how much pressure it is under. The weight of the oil and the oil height (in the forks) can also effect damping.

Both the shock and forks on the Mk2 and above are rebuildable. When new they are too soft for doing the kind of things you're doing at the MX track, so after 15+ years of wear they will really not be up to the task.

Rebuilding, revalving and respringing will give a whole new lease of life to your bike. KAIS are one company that has been used by some on this site.

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Re: Mk 2 Suspension ideas

Post by 118118 » 04 May 2008, 20:06

knackeredMk1 wrote:Damping is controlled by a system of flexible shims and holes which control the speed and amount of oil that flows in different directions according to whether the suspension is expanding or contracting and how much pressure it is under. The weight of the oil and the oil height (in the forks) can also effect damping.

Both the shock and forks on the Mk2 and above are rebuildable. When new they are too soft for doing the kind of things you're doing at the MX track, so after 15+ years of wear they will really not be up to the task.

Rebuilding, revalving and respringing will give a whole new lease of life to your bike. KAIS are one company that has been used by some on this site.
Cheers Knackered,
I have used Kais in the past. they overhauled my suspension but only back to original spec. i will give them a call again and ask for advise.

thanks,

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Re: Mk 2 Suspension ideas

Post by slider » 05 May 2008, 07:22

stu if you can jump that well i wouldn't worry about a few iddy biddy rocks on the 17th :wink: .
top pics mate 8)

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Re: Mk 2 Suspension ideas

Post by 118118 » 05 May 2008, 09:10

slider wrote:stu if you can jump that well i wouldn't worry about a few iddy biddy rocks on the 17th :wink: .
top pics mate 8)
Steve,

Jumping is the easy bit ............ landing and staying on is the hard part! :lol:

looking forward to the 17th. :D

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Re: Mk 2 Suspension ideas

Post by sparky » 05 May 2008, 10:37

118118 wrote:
sparky wrote:just out of curiosity where in coventry is that track??
Here you go:

G&P MX Park

Coventry / Ryton - G&P MX Park

Lots of big jumps including Table tops, step downs, doubles, ski jumps, etc May not be suitable for beginners

The tracks owned by UK FMX rider Gary Tayler you can find thetrackjust off the coventry airport roundabout, or M69 left at Roundabout, dont take the first turn to Ryton carry on its on the left under the bridge can't miss it.

Contact: 07775652160

Opening Days/Hours: Wed,thur,Sat,Sun starts @ 10am - 4pm

Facilities: Cafe

The track usually runs sessions Schoolboys then a125 session then 200cc-unlimited

Cost: £25 per rider

Great fun but far harder than it looks! :wink:
cheers matey i know the one you mean now been past it a few times but never been in
done the mallory track a few times but it starts to get boring after a while
crm250 mk2 designed by a genius, built by craftsmen, ridden by a plonker

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Re: Mk 2 Suspension ideas

Post by 118118 » 07 May 2008, 12:49

Thanks for all the advice guys but I have spoken to a couple of Suspension specialists today and there are no aftermarket spring available for the CRM due to its age and the springs a tapered.
My only option to harden the front end is to get springs made to order at around £90 each!

I know some people have fitted early CR 125 forks, what year fits straight in? Can these springs be up rated?

It’s all sounding like an expensive job now so it might just have to be a great green lane bike :(
But I did enjoy my motocross outing :D

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Re: Mk 2 Suspension ideas

Post by slider » 07 May 2008, 14:53

stu,davey munroe had cr (125 iirc) springs fitted in his crm forks wich came in a range of ratings,give him a p.m.as for the rear i know demon tweeks do after market springs in different i.d's and ratings might be worth some investigation :wink:

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Re: Mk 2 Suspension ideas

Post by 118118 » 07 May 2008, 15:57

slider wrote:stu,davey munroe had cr (125 iirc) springs fitted in his crm forks wich came in a range of ratings,give him a p.m.as for the rear i know demon tweeks do after market springs in different i.d's and ratings might be worth some investigation :wink:
Thanks Steve, I've sent him a PM


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