What Size Steering Head Bearings?

[Ollie1995]

Hi, I'm part way through building an XS250 but I'm struggling to find cheap bearings. The cheapest bearings I have found are 1/3 the price i paid for the bike and they are taper roller bearings. However since it's a low budget project I'm trying to source some loose bearings but cant find them anywhere due to me not knowing what size the bearings are, so if anyone could let me know what size bearings I need that would be fantastic.

Thanks, Ollie.

[Preload]

If they are ball bearings they are about 6mm or 1/4" any bearing supplier should help. Check the races as they are generally worn and pitted.

[Ollie1995]

Thanks for the reply Preload, could anyone else confirm these are 6mm, they're only £3 for 100 but it'd save me some hassle

[drewpy]

you can get pyramid taper bearings for £20, not worth saving a few pounds as the tapers offer a better riding experience IMHO

they are 1/4" 19 pieces top and bottom (not metric sized)

[Ollie1995]

That's great drewpy cheers, I'm just trying to get a rolling chassis before I start investing money into it, so these can easily be changed at a later date.

[Preload]

you can get pyramid taper bearings for £20, not worth saving a few pounds as the tapers offer a better riding experience IMHO

they are 1/4" 19 pieces top and bottom (not metric sized)

Hi Drewpy, do the taper races fit in exactly same as generally I find they are thicker than standard Yamaha bearings?

[drewpy]

Hi Drewpy, do the taper races fit in exactly same as generally I find they are thicker than standard Yamaha bearings?

you need to take out the lower seal. as they are a bit higher than standard.

much better handling. I have always changed to tapers ever since my plastic maggot got changed. transformed the handling

[Preload]

I thought they would be. Most people like the handling after fitting Tapers but it generally because they alter the trail angle so the bike steers quicker. I fit them too heavy bikes as they improve low speed handling no end.

[Cynic]

Im trying to picture how they alter the trail.

The headstock is in the same place. What changes?.

Surely the handling improves because of the better bearing. Somoother with much better high load performance as the working area to spread the load is huge compared to ball bearings.

[Preload]

What happens when you fit Tapers, they are thicker compared to standard cup bearings say they are 10mm thicker overall for both top and bottom. So the top is 5mm higher than standard so when you refit the forks which on early bikes the fork top was fairly level with the top yoke you are effectively dropping the front end 5mm ie quickening the steering and in some cases on RD's makes them very nervous indeed.

On a different point there is 10mm less steering stem thread to tighten the front end correctly which could be nasty.

The note about being smoother is true however on small light weight bikes it hardly noticeable IMO.

[Tommy xs]

been thinking of fitting tapers to my bike as they are still the originals and i had to repack & tighten them up last year as my bike failed mot on them

and this year they said their was a bit of play in them again only advisory this time, don't won't to just keep tightening them as they are over 31 years old

is their a particular brand I should be looking for, for quality

[Ollie1995]

So I've bought a load of loose bearings just to get the project going and I can make some rather more expensive investments when I move on a bit further. I'll let you know how they are when they come