Suspension or Mousse tube?

[wence]

G'day all,
Hopefully this is the right section for this question.
Just had a couple of quick blats around the back paddock after fitting second hand mousse tubes and rebuilding the motor.
It is all different now , a lot more power and a lot snappier.
Just wondering whether the mousse tubes have a tendancy to feel like they are rolling.It almost feels as if the front suspension is not right and the front is pushing through corners.
Is this normal, do you need to adjust suspension normally or is this just a feel that I have to get used to with the mousses?
Any help appreciated....
Thanks Wence.
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[swazi_matt]

THE mousse will affect suspension as you are probably increasing the rolling weight of the wheel. I have never used a mousse but have used tubliss where you are decreasing the weight and needed to adjust the clickers to compensate for the loss of rolling weight, so imagine you will need to do the opposite adjustment for mousse.

unfortunately i cannot remember which way i adjusted it, sorry

[wence]

Thanks Matt,
I was wondering that.
Mark

[bchatt]

Originally Posted by wence

G'day all,
Hopefully this is the right section for this question.
Just had a couple of quick blats around the back paddock after fitting second hand mousse tubes and rebuilding the motor.
It is all different now , a lot more power and a lot snappier.
Just wondering whether the mousse tubes have a tendancy to feel like they are rolling.It almost feels as if the front suspension is not right and the front is pushing through corners.
Is this normal, do you need to adjust suspension normally or is this just a feel that I have to get used to with the mousses?
Any help appreciated....
Thanks Wence.
__________________

Hi Wence
I'm interested that you felt big gains in power after the rebuild. How many hours had the top end done? What work did you do for the rebuild? I'm at around 140 hrs now and wondering if it'e time for a fresh piston and rings....
As for the mousse tubes - I have had them in the past and what you describe sounds to me like they are past their best - they tend to lose their density and shape over time and the front end starts to feel a bit "vague".
Barry

[ferguscawley]

I find that you need to increase your rebound damping a bit when you fit mousses. The fork compresses more as the tyre is still quite hard (compared to a tubed tyre) and so you need more rebund damping to stp the bike springing back up too fast.

fergus

[wence]

Thanks fergus I will give that a try but by the sounds of it this second hand front is maybe no good.I may go back to a UHD front tube.
Barry, I bought the bike and it had had a total rebuild from what I was told but I could never get a definite answer as to bottom end.
I did one full season and a few trail rides with it and checked th piston through the exhaust port.All seemed ok so I was going to wait until the 24hr race we had a month ago and freshen it up then.
In the second race of this season the bike nipped up(so I thought) and I couldn't start it.Upon disassembly we found the ignition side main crank bearing had disintegrated.
We checked and washed out everthing and replaced both mains as we had to leave for a week long preplanned bike trip the next day.
I did this trip and then a 2 day race and have now pulled it down completely and rebuilt it.
As I was putting it together I basically cleaned everything thoroughly and checked and double checked evrything( mostly cos this is the first total rebuild I have done).
The power valve bearing were gummed up to the point that if you tried to spin them in your hand ,they wouldn't.Needless to say the do now and I suspect that this and the thorough cleaning of the head etc together with a new plug and a well sealed exhaust all make it that bit snappier .
The other thing I noticed was that when it was pulled down the reed spacer to reed block gasket was installed back to front or upside down and was actually blocking the airway by about 8mm( effectively 15%).
Sorry to ramble on but that is what I did and all of the above has really made it a lot better.
In my opinion, check through the exhaust , but in future if I am wondering about it then it is probably due and I will be doing it.
Cheers Mark

[bchatt]

but in future if I am wondering about it then it is probably due


Those are very true words!

[iancp5]

If they're secondhand are you sure they're not worn out? They go soft with use. What wears them out is heat, which comes from speed. As you're in Oz they may have been ridden at high speed in high ambient. They should not feel like they're rolling unless you're used to tubes at high pressure, i.e. 20 psi plus.

[wence]

Not too sure what they are meant to feel like other than a deader feeling which is what I have until I push it a bit.The tyres just seem to feel like they are going to push through the corners although they have not done so yet.Just not real confidence inspiring.
I am used to 12 psi by the way.
It may just be the terrain in my back paddock but I don't think so.
Cheers Mark

[iancp5]

I don't notice mine unless they are very badly worn but then I have been using them for years. I don't notice any particular pushing. I haven't even noticed having less grip than tubes except with brand new Mousses. I 100% prefer them for the no puncture aspect and happy to sacrifice the ultimate traction if there is a difference. I did have a rear tyre start to come off but that was because I fitted the wrong size and worn Mousse!