DIY Type I Fork Seal Diver

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gocytocis
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DIY Type I Fork Seal Diver

Post by gocytocis »

This isn’t a game-changer for anyone replacing seals on their Type 1 forks, but it’s the first time I’ve had to do this job on my /5 and perhaps what I discovered will be helpful for others too.

I was looking for something more sacrificial (and cheaper!) than the often-recommended 34-36mm sockets (modified & not) as DIY seal drivers. I found that a short length of 1-1/2” ID PVC pipe perfectly mated up with the upper profile of the fork seals, & safely allowed them to be inserted with a rubber mallet no further than flush with the top of the fork sliders (as per installation instructions). The relative softness of the PVC (especially after I’d filed the edges off) means there’s no risk of damaging the machined surface of the aluminum for slider either…

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'72 R75/5
Wobbly
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Re: DIY Type I Fork Seal Diver

Post by Wobbly »

If you used P80, then you could push the seals in with your thumbs and wouldn't need the tool at all.
After 20 years as a professional bike mechanic and 30 years as an engineer I know just enough to be dangerous !
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Zombie Master
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Re: DIY Type I Fork Seal Diver

Post by Zombie Master »

Wobbly wrote: Thu Jul 12, 2018 1:17 pm If you used P80, then you could push the seals in with your thumbs and wouldn't need the tool at all.
Might be helpful to know what P80 was.
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gocytocis
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Re: DIY Type I Fork Seal Diver

Post by gocytocis »

Zombie Master wrote: Fri Jul 13, 2018 2:57 am Might be helpful to know what P80 was.
I'll confess I had to Google it.
Wobbly wrote: Thu Jul 12, 2018 1:17 pm If you used P80, then you could push the seals in with your thumbs and wouldn't need the tool at all.
Thanks for introducing me to a product I had no idea existed! Unfortunately, I don't find any local retailers I'd be able to buy it from. The online sources I found left me with the impression it's only available wholesale(?). It also looks pretty spendy too.

I did lightly coat the seals with fork oil prior to inserting & I did in fact first try to simply push one in by thumb, but I felt like I was risking the seal going in either obliquely or too far, & I didn't want to ruin the seal by having to pull it back out.
'72 R75/5
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jagarra
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Re: DIY Type I Fork Seal Diver

Post by jagarra »

Wobbly told us about P80 a few weeks ago when another discusion came up about installing seals. Got my tubes of P80 from Amazon. Price wasn't too bad for an offer of 2 tubes, under $18.00.
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Wobbly
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Re: DIY Type I Fork Seal Diver

Post by Wobbly »

P80 is a like a synthetic rubber lubricant, but it evaporates after several minutes which makes it perfect for installing oil seals and such.

You are correct. You can't buy it direct, you need a dealer and there are several on Amazon. Some might consider it pricey, but when you can install a $20 BMW oil seal perfectly straight the first time without straining or destroying the seal, then you know it's a good thing.
After 20 years as a professional bike mechanic and 30 years as an engineer I know just enough to be dangerous !
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Zombie Master
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Re: DIY Type I Fork Seal Diver

Post by Zombie Master »

Sounds like a good thing.
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Re: DIY Type I Fork Seal Diver

Post by Wobbly »

The stuff looks like skim milk, and when you apply it, doesn't seem to affect the seal at all. Doesn't even seem to "wet" the surface well enough to do anything. But when you offer the seal to the hole and push on it, WOW !!
After 20 years as a professional bike mechanic and 30 years as an engineer I know just enough to be dangerous !
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gocytocis
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Re: DIY Type I Fork Seal Diver

Post by gocytocis »

Wobbly wrote: Sat Jul 14, 2018 3:04 pm Some might consider it pricey, but when you can install a $20 BMW oil seal perfectly straight the first time without straining or destroying the seal, then you know it's a good thing.
Any sense of its shelf life? Other uses? In over 25 years of motorcycling, I've only ever needed to replace 2 sets of fork seals. The stuff would likely perish long before I could use it up...
'72 R75/5
Wobbly
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Re: DIY Type I Fork Seal Diver

Post by Wobbly »

It will last at least 4 years. That's how long I kept our first tube at the shop.

You might go to their web site and pull down the MSDS sheet. That'll tell you what they think it is.
After 20 years as a professional bike mechanic and 30 years as an engineer I know just enough to be dangerous !
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