Another Swapping / tracking issue.

[MikeS]

Junior had a bad experience through some HiSpeed, Deep , Non uniform whoops. I was close to see it and he doubled in and when the front hit the next whoop the back swapped or kicked causing the front to slam lock to lock then it got ugly....
Junior was just beat up but I feel bad as I am setup man.

Bike is a new 03 TM125E with Ohlins front and back.  Bike was broken in with 4-5 hours of race pace trail riding. Bike has WER steering dampener at 3/4 stiff setting.

I checked sag and set suspension per factory suggestions.

During race here is settings. Terrian fast pace AVG 21mph dry,rocks roots

Front
Free sag     50mm : Race sag 63mm
Rebound    12 clicks out from full slow
Compress   16 clicks out from full hard

Rear
Free sag   40mm ; Race 95mm
Rebound   18 clicks from full slow
Compress 16 clicks from full hard

Bike  was poor on choppy turns and whoops that are uneven.

Spoke to MXTech and they suggested that the rear may be packing as swapping occurs... I read forums and figured it was possible.

I reset this way and did the testing as close as we could duplicate race course.
14-18mph sections moist not wet soil/ rocks roots

Front static sag 35mm (spec 30 +/-5) Race 50mm (spec 50 +/-5)
Rebound 12
Compress 13

Rear Static 40mm Race 100mm (spec 35 +/-5 / 95 - 105)
Rebound  26
Compress 14

Junior said it is scarey this way, front skated and the back kicked over every rock. Acceleration was not smooth. Bottomed at speed. Front twitchy.

During the testing I tweeked and Tweeked. Over the same stuff.

I ended up with the same sag frt/rear.

Front Rebound  10 from full hard (slower than before)
         Compress 9 from full hard (firmer than before)

Rear Rebound   14 from full slow (slower than originally)
        Compress  10 from full hard (firmer than originally)

He feels confident this way. I hope JC from MXTech will have time this weekend to check the suspension out as we are running a GNCC.

I welcome comments from any of you guys that have gone through this.

We had our RM85/100 done by MXTech and I have not turned a clicker since I put them on and Junior can slam anything with sure confidence. I hear the Ohlins are great suspenders and would like to get them to work without major surgery :scream:

 

 

 

[jaguar]

If junior is lighter than an average 125 rider then lighter springs would be in order.
Otherwise I'd say either the compression is too slow or the rebound is too fast (or a combination of both).
Also you should watch to see if the rear end is bottoming out when landing from jumps. If not, then that's another sign compression is too slow.

 

[georgieboy]

Looking at the figures front rear, I notice that the front is with 50mm low for a mx bike and the rearspring is cranked in tomuch for getting the 95mm.
So with the rear you are already working with a stiffer first compression.
Front maybe under sprung and rear over sprung.

 

[MikeS]

Thanks for the input.

We road the GNCC here in PA. Junior finished mid pack(discouraged some).

He said when going slow he was beat up but at speed it was good. He said there was onlt a few whooped out sections and the bike tracked straight but pounded hard in the rear some.

This is what we had at the race

Frt    sag 50   mm
Rear sag 100 mm

Front Rebound  10 from full hard (slower than before)
         Compress 9 from full hard (firmer than before)

Rear Rebound   14 from full slow (slower than originally)
        Compress  10 from full hard (firmer than originally)


I assume we were stiff on compression.

I plan on softing the front on compression some (4 clicks) and 2 clicks on rebound. Then add some oil to help the big hits. Junior said the front skated in turns that got choppy. So I hope that will make it more plush and have less bottoming going into the whoops.

As for the rear I may just soften it a tad on compression.


The sag the front is perfect in spec for Junior per the manual. .41 springs and he is 165-170 lbs on the bike. Rear I think are 5.1 but not 100% sure. Rear sag is close. Most guys say run more race sag. Closer to 105. It is hard to measrue that close. I think 10 lbs of mud that collects on the bike is going to change it more.

Again thanks for listening.


 

 

[georgieboy]

Well Mike S,
i think you dealing with yr kids suspension very professional.
Despite the lack of input, i think you will succeed.
I ve read your post with intrest. bibi

 

[jaguar]

What I did with my bike is adjust the compression to be just slow enough to:
1. not allow harsh bottoming landing from jumps
2. allow the front to jump steep whoops and not absorb the first one too much

To have the front with enough compression resistance to skim whoops leaves it just a tad stiffer than what I like for small bumps.

The rear on my bike had too little rebound resistance and so the rear end would sometimes dance a bit side to side instead of tracking straight. After the final adjustments on the rear it felt strange to not feel the track as much and it to be so controlled.

 

[MikeS]

Jaguar

Thanks for the tips.... Just got back from racing.

Good ole New Jersey sand harescrables...miles of deep whoops etc.

The bike was flawless. Junior just needs to gain stamina to ride the new level the bike allows.

Final settings have the clickers frt and rear softer from stock, more rear rebound (slower), more front preload + 8mm each leg and took air chanber from 115mm to 100mm.

these Ohlins now work as well as they look :)

 

[jaguar]

cool!

 

[DEANSFASTWAY]

Mike Whered you go to chatsworth? Maybe now the muilew long whoops sections have finally broken in the Suspension .

 

[MikeS]

Originally posted by DEANSFASTWAY
Mike Whered you go to chatsworth? Maybe now the muilew long whoops sections have finally broken in the Suspension .

 

Yep Chatsworth was the place. I figured that would be the best test for my setup :scream: . It was amazing to see those whoops go from the nice 5th gear blasting fun stuff to 3rd gear 5ft deep mounds of sand.....more like a mile long stretch of doubles,triples.....