They are called needle bearings because in all rocking applications they will give you "the needle" !
Gearbox woes
- Thread starter Albervin
- Start date
I guess we better all change our big ends to slipper bearings then if that is the case ...Last time I checked, the crank and rods of my engines operate very much on a reciprocating basis. So what has more shock loading....the big end, or the front end as you go over a bump in the road...?
I think with a roller (needle) type bearing in the girdraulics the heaviest loading would impact on the same rollers. In a roller big end the rollers are actually rotating and rolling around the crankpin so that heaviest loading is shared out over all rollers thought the cycle. Plain bearings don't normally rotate, have a large surface area to spread the load and a film of lubricant between the load surfaces.
I'm just stating a personal point of view based on 40+ years working on slow moving machinery. I'm not an automotive Engineer, but, John, I suspect the U-joint bearings actually rotate (I have a friend who works for GKN designing drive shafts, I'll ask him) and Greg, how many modern engines use rolling element big ends, and when people modify Vin cranks to "one piece" do they use rollers or bushes?
Sometimes the wrong bearing is the best of a bad bunch, I recently changed the swinging arm bearings on the Egli - taper rollers like a "proper Vin" - they were notchy and completely shot, but I can't think of a better option.
H
Sometimes the wrong bearing is the best of a bad bunch, I recently changed the swinging arm bearings on the Egli - taper rollers like a "proper Vin" - they were notchy and completely shot, but I can't think of a better option.
H
I was thinking of maybe more than just two bearings per link, ie 4. I don't do a big mileage now so, And I will try to miss the Potholes !! Cheers Bill.
Obviously with my last comment I was just joking......Tapers in the swing arm suffer more from marks caused by corrosion than anything...they probably move through less angular travel than the links in the forks. As some of you know I put sealed bearings and needle rollers in the links of the racer I built.....but on a racer you can experiment a lot more than you can with a road bike. Roller bearing cranks were very popular years ago....hardly used any more....I would say that descent oil pumps, top quality oil filters, and better oils have all sorted these issues out these days, as modern engines coupled with good air filters last forever.....don't see to many Smokey clunkers on the roads anymore.
It would be interesting if the load on the fork spindles could be accurately measured.I think that the load direction would not be in the axis that most would assume it to be.
As for the amount of load on the spindles, in normal use isn't the load of the bike taken on the suspension springs--ie anchored at the eccentrics at the top and the Girdraulic leg at the bottom. So how much load is there at the spindles??..John
As for the amount of load on the spindles, in normal use isn't the load of the bike taken on the suspension springs--ie anchored at the eccentrics at the top and the Girdraulic leg at the bottom. So how much load is there at the spindles??..John
I think Bill might have changed the thread topic a bit back.
Corrosion in poorly lubricated bearings is often a reddish colour not brown, and is caused by dry metal parts rubbing instead of rolling, it's corrosion Greg, but not as we know it
(fretting corrosion - other types of corrosion are available).
NKT I don't know, but there must be some or we wouldn't wear out the bushes - this needs to be seen by Rob and Co the suspension men.
H
Corrosion in poorly lubricated bearings is often a reddish colour not brown, and is caused by dry metal parts rubbing instead of rolling, it's corrosion Greg, but not as we know it
(fretting corrosion - other types of corrosion are available). NKT I don't know, but there must be some or we wouldn't wear out the bushes - this needs to be seen by Rob and Co the suspension men.
H
I think Rob Staley might have done some calculations on the loads in the Girdraulic bearings. I'll ask him later, just off to the AGM.