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The TTR250 FAQ web pages -> TTR250 -> Wanted adverts -> REAR SHOCK
Post Info TOPIC: REAR SHOCK
vwanjau


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REAR SHOCK
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Hi Guys,

I have been buying the rear shock seal(seal head) and repairing the shock for 3 times now, but it ends up leaking.

What could be causing the seal to get worn out fast? runs for like 3 months then starts leaking again.

Can I use honda xlr 250 Rear Mono shock instead? Repairing the shock every three months is costing me Money and time.

 

Kind Regards



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ttboof


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Pitted or damaged chrome on the shaft? 

Not something that happens much normaly



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TTRfan


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Sorry to hear of your problem Vincent.

I was going to suggest the same as Les in that the chrome on the shock shaft is damaged. You may have to look hard to find the damage although usually a finger-tip test will pick it up.

It seems unlikely that three new seal heads would be faulty so it has to be an issue with the shock itself. Presumably the leak is evidenced by oil weeping down the shock shaft?

The TTR shock is special (like panels) and many owners have tried to find one from another bike that would fit but not heard yet of anyone succeeding.

Any shock from any other bike could be made to fit given sufficient engineering skills and resources.

Brian



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vwanjau


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Hi Guys,

 

By saying chrome you mean the housing that holds the shock oil?

Yes the shock oil drips down from the shaft down. I am forced to ride slow now as the shock is very low with no shock oil to suspend it 

 

Kind Regards



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mossproof


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The chrome is the shiny coating on the centre shaft of the shock. If it is pitted or badly scratched by rust or stone damage, the oil seal quickly gets damaged as it slides over the rough surface and out comes the oil. Unfortunately, if it is damaged, the shock is scrap.

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vwanjau


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Thanks for the advice. Now after a huge percentage of the Oil leaked, the shock is not leaking any more.

But its not very strong,and the compression can really go low to an extent the rear site comes into contact with the tire when I hit a bump on high speeds.

Not sure how to fix the oil leak though.



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TTRfan


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Have you been able to check the state of the chrome on the shock shaft?

It sounds as though it is damaged and/or flaking and will need cleaning and re-chroming.

Brian

 

Shock_part_names1.jpg



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vwanjau


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H TTR fan,

De-assembled the shaft again. Please find the pics of the shock attached.

Kind Regards



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TTRfan


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It is difficult to tell from photos but the inside of the shock body looks quite scored. Is it just superficial or are any of the grooves deep enough to allow oil to leak around the seal head outer oil seal? 

If your shock shaft is as good as you say then oil won't be leaking between the seal head and the shaft so it has to be leaking elsewhere.



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vwanjau


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Hi,

The chrome is just abit worn out(superficial) but there are no groves that can let oil to leak through the outer seal head.

At the middle of the seal head, the condition of the shaft would affect the leaking? In my case, it has no bruises nor crossion. Also it is not bent.

At the piston level, the first section of the image you sent, would that have any impact on the leakage?

Kind Regards



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vwanjau


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Also what is the importance of the Nitrogen Gas?


Thanks for taking time to brainstorm on my shock issue.

 

Kind Regards



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ttboof


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Nitrogen is denser than air do takes longer to go through seals.  It doesn't have water in it. Air can heat up faster than nitrogen 

However  due to the small amount in the ttr shock it may not make much difference.  Haven't tried it 



-- Edited by ttboof on Tuesday 19th of May 2020 10:11:36 AM

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vwanjau


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Thanks super guru for the info.

 

I hope this time it does not leak, trying to use orings at both the top(piston) and the seal head to make it more firm.

 

Kind Regards



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ttboof


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Mine was done by a suspension place said it was pumped to 140psi with nitrogen.  I was told it would need a service after 12 months it's now three years still seems OK 



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