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Noticed a slight weep from around the rear damper.

Had a look at my records and it's just short of 15,000 kilometres since I had my suspension serviced and 'heavier' springs fitted to the forks so decided it was time to get it serviced again.

I can't believe the difference! You don't realise how much the suspension deteriorates until you get it serviced. They replaced fork seals as a precaution, the weepy rear seal and wiper. The oil was pretty shagged, front and rear.

My tip: if your bike is getting the miles up, consider getting the oil changed irrespective of whether you are running Ohlins or Sachs/ Marzocchi suspension. Getting forced through tiny orifices is not good for oil.

I asked about the leaky seal at the back and they expressed surprise. They said that Ohlins generally lasts well (unlike the claims of some) but thought the heat might well have affected the seal.

Next up is the 25,000 k Ducati service (it's been nearly a year and 14,500 k since the last service, although I do oils and filter every 5,000 k).
 

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I am a believer in servicing suspension once it leaks. I have 11k on my SS and it seems fine. After nearly 300k motorcycle miles, I've never felt a difference after changing suspension oil even after a seal was weeping for weeks or for (one bike) years.

I will admit I've never owned a bike with Ohlins so I have limited experience and have no opinion about S models.
 

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Surely there’s not that much difference in fluid life, etc. between fork manufactures. I believe they all work in a similar manner. If I’m wrong, I stand corrected.
On my mountain bike, I’ve used Push Industries services to custom valve Fox products. Made tremendous difference in performance for that application.
 

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Surely there’s not that much difference in fluid life, etc. between fork manufactures. I believe they all work in a similar manner. If I’m wrong, I stand corrected.
On my mountain bike, I’ve used Push Industries services to custom valve Fox products. Made tremendous difference in performance for that application.
Totally agree. They absorb the same bumps and, one would expect, go up and down the same number of times. Damping works the same, irrespective of brand, forcing oil through small holes to convert inertia into heat.

I can’t see the point in buying a scalpel and letting the edge dull...
 
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Have my 30000km Desmo service due and will be having my suspension serviced by podium racing at the same time. I am currently changing chain and sprocket (front only surprisingly the rear is still fine.) I have a big ride in 2 weeks if the floods allow then she goes in for the big nip and tuck. I expect her to be like new again.
 

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Have my 30000km Desmo service due and will be having my suspension serviced by podium racing at the same time. I am currently changing chain and sprocket (front only surprisingly the rear is still fine.) I have a big ride in 2 weeks if the floods allow then she goes in for the big nip and tuck. I expect her to be like new again.
that's 30000 km on the original sprockets and chain?

the front on my CB500X wore out way before my rear as well, but due to off roading creating a stretched link causing tightness in the chain. This caused the chain to really dig into the front sprocket, and since it's smaller, the teeth had to take on more of the tension force, whereas the rear sprocket had more teeth to absorb the same force. Each front tooth is now shaped like a wave instead of a symmetrical mountain. I'll post pics whenever I get around to replacing it.
 

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I've never felt any difference before or after changing fork oil.

I do recommend changing it once the seals weep. :wink2:
 

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It’s recommended to change the oil around 15-20k miles. I had a refresh of oil at 20k miles, and new ohlins springs at 35k miles with new oil... didn’t feel any different. The rear never needed a rebuild, even at 35k miles. The biggest difference was a proper set up for my weight. Dust seals my need changing a few times though...

If I had only done 15,000km on a rear or front shock and it was leaking, I wouldn’t be happy.
 

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Suspentions are still a mystery to me. I have 27,000 miles on a KTM 990 Super Duke, and just recently, had the fork fluid changed because of the mileage, and age, it had to be shot. I can't tell any difference; except now the front end squeaks. I wish I had let it alone. (I took the forks off and took them to a local shop)

"Feel" is not a standard unit of measure. The forks, after a fluid change, may indeed be better. But I often wonder, When someone changes brake fluid, or fork fluid, or the air filter, etc.... how much of what is felt is really the placebo effect?

Why doesn't the front shock fluid on my pick up truck need to be changed at 20,000 miles? Why doesn't the rear shock on a motorcycle require fluid change at the same interval?

Why can you see thru glass? Why can you see a reflection of yourself in a mirror? So much I don't understand.
 

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I've always waited for the seals to leak to change the fluid and seals. Never been an issue and never felt a difference.

I now always use OEM seals. I once used aftermarket, and they leaked after 3 weeks.
 

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Suspentions are still a mystery to me. I have 27,000 miles on a KTM 990 Super Duke, and just recently, had the fork fluid changed because of the mileage, and age, it had to be shot. I can't tell any difference; except now the front end squeaks. I wish I had let it alone. (I took the forks off and took them to a local shop)

"Feel" is not a standard unit of measure. The forks, after a fluid change, may indeed be better. But I often wonder, When someone changes brake fluid, or fork fluid, or the air filter, etc.... how much of what is felt is really the placebo effect?

Why doesn't the front shock fluid on my pick up truck need to be changed at 20,000 miles? Why doesn't the rear shock on a motorcycle require fluid change at the same interval?

Why can you see thru glass? Why can you see a reflection of yourself in a mirror? So much I don't understand.
:laugh::laugh: Why indeed :laugh::laugh:
 

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I've always waited for the seals to leak to change the fluid and seals. Never been an issue and never felt a difference.

I now always use OEM seals. I once used aftermarket, and they leaked after 3 weeks.
Glad to hear it. I thought I was alone.
 

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Discussion Starter #13
It’s recommended to change the oil around 15-20k miles. I had a refresh of oil at 20k miles, and new ohlins springs at 35k miles with new oil... didn’t feel any different. The rear never needed a rebuild, even at 35k miles. The biggest difference was a proper set up for my weight. Dust seals my need changing a few times though...

If I had only done 15,000km on a rear or front shock and it was leaking, I wouldn’t be happy.
Suspension experts all agree that suspension should be serviced every 10,000 kms. More often on the track, less often on the street. After talking to people like Dave Moss I settled on 15,000 ks/ 10,000 miles.

I'm surprised you felt no difference servicing at 35,000 ks with new springs. I've adjusted damping through the 15,000 ks and there is a measurable difference. You have to increase damping to compensate for thinning oil.

Although I felt disappointed about a leak at 15,000 ks after servicing I understand my bike gets ridden hard, including Australian summer days were the ambient is well over 40C. As I was planning to service at 15,000 ks it doesn't matter. The suspension guys checked everything was OK (it was) and replaced seals and wiper.

I cannot understand why most riders think 15,000 ks on engine oil is too much and replace oil and filter every 5,000 ks but are happy to let their suspension oil to go so long.
 

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Discussion Starter #15
...Why doesn't the front shock fluid on my pick up truck need to be changed at 20,000 miles?..
That would be the same reason your vehicle's transmission is sealed for life, there are no grease nipples on suspension components, tyres last 8 times as long and a motor six times the size has less than three times the power.

...Why doesn't the rear shock on a motorcycle require fluid change at the same interval?..
It does. Forks take more of a pounding, but.
 

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Discussion Starter #16
one word why: combustion
Combustion = burning so the oil is lost. You can just top the oil level up if that's why you change your oil.

The reason we change oil is its molecular structure breaks down. In a motor, this is largely due to shear forces. Synthetic oils have come into vogue for high-performance applications because they are molecularly different, not because they are less likely to burn.
 
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I support the idea that sport bike suspension should be serviced and oils changed. I take advice from the experts (I choose my experts carefully and don’t just agree with whats thrown out and written) I do have to admit that if I rode a cruiser or just used my bike for straight line riding and commuting I probably would not bother changing oils till I had a fork seal leakBut here’s ,s the thing. I want my suspension to protect me when I need it to. When I’m leaned over in the canyons I want my suspension to do its job and keep that rubber on the road. I need to trust that if the road surface turns to corrugated sh1t ( the road melts here from the heat and when heavier vehicles go around corners it pushes it up into ridges) it’s going to soak it up. I expect to feel a difference when my oil is changed. If I don’t i will put my hand up and let you all know .
 

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I don't think you'll feel a difference when the fork/shock oil is changed. However, only a guess since I haven't owned Ohlins.
 

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Combustion = burning so the oil is lost. You can just top the oil level up if that's why you change your oil.

The reason we change oil is its molecular structure breaks down. In a motor, this is largely due to shear forces. Synthetic oils have come into vogue for high-performance applications because they are molecularly different, not because they are less likely to burn.
You make a good point. The oil in the engine also goes through many more cycles since the engine runs thousands of RPMs vs suspension that has a few cycles per second.

But my issue regarding combustion wasn't so much for burning it off, which is a good point. The issue is heat and soot. All those burned hydrocarbons that dirties the oil as well as the heat cycles on it.
 
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