The friendly "dumb" bike questions thread

The friendly "dumb" bike questions thread

Author
Discussion

talksthetorque

10,815 posts

136 months

Wednesday 1st September 2021
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Just get a new seal when you're popping out for some new underpants!
Well done on not really crashing.


Krikkit

26,544 posts

182 months

Thursday 2nd September 2021
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talksthetorque said:
Well done on not really crashing.
This! Nice work. I'd echo the sentiments to just replace the rubber seals. Had the same issue with my push-bike and that was all that was needed.

To switch topics, anyone got a suggestion what to do with an old but usable lid? It's not really saleable as I dinked one of the spoilers on the back, plus it's a bit old, but still wearable for someone with a big enough head. I was looking for a charity project or something but couldn't find one. I might see if the riding school I learnt with could use it.

the cueball

1,203 posts

56 months

Thursday 2nd September 2021
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Krikkit said:
To switch topics, anyone got a suggestion what to do with an old but usable lid? It's not really saleable as I dinked one of the spoilers on the back, plus it's a bit old, but still wearable for someone with a big enough head. I was looking for a charity project or something but couldn't find one. I might see if the riding school I learnt with could use it.
I used to take my old lids to the fire/ambulance service so they could use them to practice cutting up/taking off/working with them etc.

Dunno if it was any help to them, but they always thanked me and took them off my hands..


RizzoTheRat

25,199 posts

193 months

Thursday 2nd September 2021
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anonymous said:
[redacted]
The seal on the piston maybe, but surely the reservoir shouldn't ever be under pressure should it?
I always assumed the piston sucked from the reservoir and pressurised the lines but the seal on the reservoir was designed to accommodate the volume changing but not take ay pressure. My rear reservoir's plastic.

tvrolet

4,279 posts

283 months

Thursday 2nd September 2021
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If we're talking about the 'seal' on the reservoir of a bike master cylinder, then it's a bellows-style thingy and there is no expectation of pressure in the reservoir at all, above or below the 'seal'. Loads of cars don't have this bellows arrangement/'seal' and the reservoir just has a small vent hole on the top. But car's aren't expected to lean over or pull wheelies or stoppies etc (or fall over) so there no risk of fluid coming out the vent hole.

Bike reservoirs also have a vent hole (sometimes just a notch in the cover) so the reservoir contents are at normal air pressure, and all the 'seal' does is separate the fluid from the fresh air but the bellows arrangement can expand as the fluid level drops, and contract if it expands - it's just a barrier between the fluid and the air. If it's leaking under this 'seal' then either it's buggered or the lid wasn't screwed-down tight enough...but there's no pressure on either side of that 'seal'.

But there is also a seal (usually an o-ring) on the master cylinder itself, and that will be under big pressure when braking, but here the fluid's going to be coming out the cylinder itself and not the reservoir.

Northernboy

12,642 posts

258 months

Thursday 2nd September 2021
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anonymous said:
[redacted]
It shouldn’t come past the seal on the master cylinder, it’s not under any pressure.

Low Pro

200 posts

162 months

Friday 3rd September 2021
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Can I ride on the North or south circular with L plates? Moving to London, passed the CBT and Theory just need some practice before DAS.

HairyMaclary

3,671 posts

196 months

Friday 3rd September 2021
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Low Pro said:
Can I ride on the North or south circular with L plates? Moving to London, passed the CBT and Theory just need some practice before DAS.
If you mean the a406/a205 yes you can.

Baptism of fire tho. Good luck!

Northernboy

12,642 posts

258 months

Friday 3rd September 2021
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Low Pro said:
Can I ride on the North or south circular with L plates? Moving to London, passed the CBT and Theory just need some practice before DAS.
You can, but I’d not recommend the fast bits of the North one unless your bike can comfortably do 60mph.

Much of the South Circular is residential streets, so manageable on anything at all.

Pat H

8,056 posts

257 months

Friday 3rd September 2021
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ZetecTDCI said:
Suspect cost has a lot to do with it. The honda cbx750 had hydraulic tappets iirc.
Indeed it did.

I have a 1986 CB700 Nighthawk, which has a de-stroked CBX motor and retains the hydraulic tappets.

It also has a shaft drive, so there really is very little by way of routine maintenance.


Seight_Returns

1,640 posts

202 months

Tuesday 7th September 2021
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So which modern bikes have "old fashioned" lockring adjustable tappets rather than shim and bucket design ?

I know of Honda NC750, Moto Guzzis, the current Royal Enfield 650 Twins. Anything else ?

Abdul Abulbul Amir

13,179 posts

213 months

Tuesday 7th September 2021
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I've just noticed a small arrow pointing upwards next to the top caliper bolt on my gold brembo front brake calipers.

Does this denote which way up the caliper goes or is it likely that bolt is reverse threaded?

Amused2death

2,493 posts

197 months

Sunday 26th September 2021
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A couple o friendly dumb questions for the more knowledgable amongst us.

1, Will noise cancelling inner ear headphones work to counteract wind noise?

2, I'm an "All the gear all the time" type of rider, but sometimes I'd like to go out in jeans and throw something protective over the top so I can take them off at the other end. Question is....Is it just a case of ordering something a few sizes larger so it'll go over the top of jeans or are there effective protective "overgarments"? If so, how does the sizing work? i.e. if I was say a 34 waist would I order a 34 or go larger?

Cheers all smile

talksthetorque

10,815 posts

136 months

Sunday 26th September 2021
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Amused2death said:
A couple o friendly dumb questions for the more knowledgable amongst us.

1, Will noise cancelling inner ear headphones work to counteract wind noise?

2, I'm an "All the gear all the time" type of rider, but sometimes I'd like to go out in jeans and throw something protective over the top so I can take them off at the other end. Question is....Is it just a case of ordering something a few sizes larger so it'll go over the top of jeans or are there effective protective "overgarments"? If so, how does the sizing work? i.e. if I was say a 34 waist would I order a 34 or go larger?

Cheers all smile
1. I've just bought some earbuds with noise cancellation, however, i\ve also just knackered my knee so don't want to get out on the bike yet.

One thing I have noticed is on a train they are not as effective at noise cancellation as foam insert plugs.
I use them for work, so you can still hear what you need to, and drown out the damaging repetitive noise of machines and high volume extraction units. And for this they are decent, if they work OK on the bike then it's a bonus.


2. You can buy Kevlar jeans that look like normal-ish jeans. I'd think footwear is more of a problem than trousers if you want to go "out-out"

Krikkit

26,544 posts

182 months

Sunday 26th September 2021
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Amused2death said:
2, I'm an "All the gear all the time" type of rider, but sometimes I'd like to go out in jeans and throw something protective over the top so I can take them off at the other end. Question is....Is it just a case of ordering something a few sizes larger so it'll go over the top of jeans or are there effective protective "overgarments"? If so, how does the sizing work? i.e. if I was say a 34 waist would I order a 34 or go larger?

Cheers all smile
I have textiles which are loose enough to comfortably stick trousers on with them as they have zip in liners. But they're also not too big to make me look like a tit.

I could probably put a sensible pair of jeans under my leathers but I wouldn't go very far.

airsafari87

2,607 posts

183 months

Sunday 26th September 2021
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talksthetorque said:
2. You can buy Kevlar jeans that look like normal-ish jeans. I'd think footwear is more of a problem than trousers if you want to go "out-out"
I have a pair of Bull-it single layer kevlar jeans and for all intents and purposes are exactly like a normal pair of jeans to look at and wear. I havent crashed in them yet though so can't vouch for how well the stand up to a crash, but I believe they onenof the higher 'protection'??? Ratings that you can get.

Footwear wise I have a set of TCX goretex plimsole thingys which have some fancy Dan footbed and D30 ankle protection. They look pretty much like a pair of leather Converse or similar.

Amused2death

2,493 posts

197 months

Sunday 26th September 2021
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I've got a pair of part lined jeans with knee and hip pads in, plus textile trousers also with pads in, but these fit well and I can't get anything on underneath them.

I was wondering about wearing ordinary jeans then having something protective with pads over the top of the jeans.

Cheers for your thoughts. smile

hiccy18

2,690 posts

68 months

Monday 27th September 2021
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I used to use a pair of Alpinestar textile overtrousers that worked as you ask, they had a big zip down each leg and it took seconds to put them on over a pair of jeans or trousers, really handy for commuting. I used them for yonks but now they've been kept for dog walking when it's chucking it so I'll take the armour out.

Amused2death

2,493 posts

197 months

Monday 27th September 2021
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Cheers Hiccy18, now off to take a look and see what I can find.

BigGingerBob

1,701 posts

191 months

Friday 1st October 2021
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When are helmet sales usually on? I want a new helmet, a Shoei GT Air 2 but they are fiercely expensive.
Are there specific times and sites to look out for?