Thorn Cycles Forum
Community => Rohloff Internal Hub Gears => Topic started by: crg on July 28, 2022, 04:06:34 PM
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Hello,
Questions on Rohloff Oil Drain Screw.
1. Size & thread pitch: M6 x 1
2. Length: 6mm - not sure. Based on eye-balling photo
3. Material: aluminum or steel or stainless steel?
Thanks
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Are you considering making your own?
Best
Matt
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I suggest you buy a real Rohoff one. I have a couple spares in case I drop one that gets lost.
If I recall, Dave W (former mechanic at SJS) said that the newer ones had a shoulder so that the screw could not be threaded in too far. Looking at the photo, it does look like a small shoulder on it.
https://www.rohloff.de/en/shop/product-detail?tt_products%5Bproduct%5D=164&cHash=002cc1750845eda9c8a01b8bfc2b19a4
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Are you considering making your own?
Best
Matt
Don't own a Rohloff hub, yet. Details will help in choosing a screw for Shimano hubs. Seems Rohloff is meticulous.
I suggest you buy a real Rohoff one. I have a couple spares in case I drop one that gets lost.
If I recall, Dave W (former mechanic at SJS) said that the newer ones had a shoulder so that the screw could not be threaded in too far. Looking at the photo, it does look like a small shoulder on it.
https://www.rohloff.de/en/shop/product-detail?tt_products%5Bproduct%5D=164&cHash=002cc1750845eda9c8a01b8bfc2b19a4
See previous answer.
Issue is not the cost but shipping + 50% duty on the total.
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See previous answer.
Issue is not the cost but shipping + 50% duty on the total.
Where are you that's subject to 50% duty?
If you have, or get, a Rohloff, then you may as well use the correct screw, whether that's buying replacement or doing what many do and re-use the original.
Likewise a Shimano 11.
If you're tapping an Alfine 8 to make it oil rather than grease lubricated, then any matching grub screw will do, there';s always a bit of clearance under the shell, you'll have to google that and it is of course at your own risk.
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See previous answer.
Issue is not the cost but shipping + 50% duty on the total.
Where are you that's subject to 50% duty?
If you have, or get, a Rohloff, then you may as well use the correct screw, whether that's buying replacement or doing what many do and re-use the original.
Likewise a Shimano 11.
If you're tapping an Alfine 8 to make it oil rather than grease lubricated, then any matching grub screw will do, there';s always a bit of clearance under the shell, you'll have to google that and it is of course at your own risk.
India.
Drilling 8-speed Shimano hubs.
Back to topic.
What is the length of the screw?
What is the material used?
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India.
Drilling 8-speed Shimano hubs.
Back to topic.
You should make that the topic. What has it to do with a Rohloff drain screw?
Plenty of advice on the internet on how to convert a Shimano to oil bath, I suggest you follow that. The drain screw doesn't have to be specific to anything other than the tap you use. Stainless steel would be the obvious material, but you're only plugging a hole, you could do that with a bit of tape over the top.
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See previous answer.
Issue is not the cost but shipping + 50% duty on the total.
Where are you that's subject to 50% duty?
If you have, or get, a Rohloff, then you may as well use the correct screw, whether that's buying replacement or doing what many do and re-use the original.
Likewise a Shimano 11.
If you're tapping an Alfine 8 to make it oil rather than grease lubricated, then any matching grub screw will do, there';s always a bit of clearance under the shell, you'll have to google that and it is of course at your own risk.
India.
Drilling 8-speed Shimano hubs.
Back to topic.
What is the length of the screw?
What is the material used?
The length of a Rohloff hub screw does not matter, the Shimano hub shell thickness is more important for that application.
Material, I agree with PH, stainless is less likely to have a corrosion problem, but occasionally you hear of people having a dissimilar metal problem with aluminum casings and non-aluminum bolts threaded into them. I put blue (removable) thread locker onto my Rohloff screw before I install it. I have been informed that there is a better oil-resistant threadlocker, but I just keep using what I have.
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It is important to order Rohloff's own screw because of the special Locktite on it – without it, oil will begin leaking from the hole. And no, you can't buy your own approved Locktite to put on the screw, because the Rohloff screw's Locktite number is an unusual one that costs a great deal and is only realistic for industrial clients to buy.
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Maybe I am using the wrong threadlocker, but I have not had a dissimilar metal corrosion problem and I do not have leakage at the screw either.
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Never had a leakage problem or one coming loose. I don’t think the early ones had loctite in fact I recall being recommended to use ptfe tape at one point. I tend to reuse them a couple of times.
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It is important to order Rohloff's own screw because of the special Locktite on it – without it, oil will begin leaking from the hole. And no, you can't buy your own approved Locktite to put on the screw, because the Rohloff screw's Locktite number is an unusual one that costs a great deal and is only realistic for industrial clients to buy.
mickeg has already posted the link to the long thread on this, with useful contribution from Thorn's then Workshop Manager, it's worth a read. I just use a fresh Rohloff screw each time, I add a few when I'm placing a SJS order, it's a minor expense and keeps it simple.
None of this has anything to do with the OP's requirement to find the best option for a Shimano hub. I'm pretty sure Shimano's 11 speed hub had a different screw tot he Rohloff.
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Shimano's oil port bolt is M6 x 1, 4mm long.
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Drilling 8-speed Shimano hubs.
I use Rohloff drain screws on my Shimano 8-speeds, because I got them in a bulk packet (maybe 10 ?). Easier than trying to find another type of screw. Nylon screws can also be used, see the link at the end of this post.
If you're tapping an Alfine 8 to make it oil rather than grease lubricated, then any matching grub screw will do, there';s always a bit of clearance under the shell, you'll have to google that and it is of course at your own risk.
Yes. If drilling a Shimano 8, the location is fairly critical because they have steel parts (ratchets?) force fitted into the aluminium alloy shell in some places. I used this link as a guide when I converted my Shimano gear hubs to oil lubrication:
http://www.astounding.org.uk/ian/hubgear/oilport.html
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The plastic used needs to be oil and UV resistant.
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The plastic used needs to be oil and UV resistant.
I wouldn't bother too much about oil resistance, as there are already plastic parts inside Shimano and Rohloff hubs, and even in Sturmey-Archer hubs from the 1950's.
Because of this, if using oil lubrication inside Shimano hubs (and Rohloff) you should be careful about the composition of the oil you use. My own choice is a synthetic gear oil, other people have used hydraulic fluid, apparently with no problems.
UV resistance might possibly be a problem on a nylon screw outside the hub, but the poster of the link I provided didn't seem to have any issues. If they do degrade under tropical sun, they are cheap enough to be replaced every few years. And Sturmey-Archer used plastic oiler caps on their 3 and 5 speed oil-lubricated hubs in the early 1980's, I still have some of these, no problems after about 40 years of use.