CSR front suspension rocker bearing modification

[Hanns Per]

I always had problems with the rocker bearing. first after 3 years in 2009 with approx 45K km. The spigot and the  oilbush (sintered bronze) got stuck. Thereafter I fiddled stupidly along greasing until  found out this winter greasing oilbushes is wrong. I looked for alternatives also because these bushes are more suited for rotational and less for oscillating movements. I found needle roller bearing and this is what Install this winter: full complement open end needle roller bearings B 1212 (ID 3/4 OD 1 inch width 3/4) 3 pcs.  per rocker from Koyo but also available from others when you search, as a spigot I use a piston bolt OD 19mm and length 68mm, thie inner diameter of the piston bolt is somewhat larger thant the original piston bolt I made a sleve from a 0.3mm aluminum sheet. As a thrust washer I use  Iglidur W300 WTI-1220-01 washers ID 3/4 https://www.igus.at/product/131.  look forward how it works our this summer

questions welcome Hanns Per

on the left You see the damaged spigots and removed bushes and an new bushes with new spigot in it and the bolt

[Tazio]

Hanns Per.

Thanks for sharing, good data for the archive 

[Toughie]

Oh, well done Hanns Per, and thanks for the information.

It just makes me think that's something else I need to worry about.

[vertew]

Hi Hans Per - you must be a mind reader ...  was just looking at the rocker bearings in my CSR, noticing a tiny amount of play and thinking that packing with thick silicone grease might be a good option ... perhaps not.  I'll take a look at your solution, cheers !   

[Hanns Per]

I would be more concerned about freezing of the spigot and bronze bearing. Bronze bearings (oillite) are reasonable cheap and not difficult to replace. If your spigots are still OK then this might be the easiest and cheapest solution and presumably good for the next 20.000 km or so. Good luck Hanns Per

 

[vertew]

I've yet to remove them to take a look, but I'll do that as that car is already in bits while I'm refreshing rear suspension.

A contact from a CSR racing team (Leo's Motorsport) has offered to make up some new oilite bushes / spigots, something they do from time-to-time for their own cars.  I'll probably go this route as it seems least effort.  I'll share how this works out + price ...

tks, Andrew.

[vertew]

Hi Hanns,

Could you share which a part / source for the 'piston bolt' (sometimes called 'gudgeon pin' in UK) you used?  Most gudgeon pins seem to quote just a part number, not dimensions (esp length).

Many thanks.

[Hanns Per]

first thought I had was it needs to be a gudgeon pin because of the surface hardness which is needed to carry the load of the needle rollers. Then I asked a friend who restores historic motorcycles an he gave me the address of this company:  Dümpert Kolben  https://www.gelbeseiten.de/gsbiz/6a9e9c0a-8220-4c28-8177-71e81cf140f4 The company has no website. I gave them a call and asked for a gudgeon pin with the desired dimensions and the lady on the phone told me what she has 19mm OD bolt which is a few 1/10th of mm longer than the original  Caterham bolt. I do not know if this is connected to a part number and I do not think so. They carry thousands of bolts and pistons for historic vehicles and I think once upon a time it was not so sophisticated with partnumbers :-) hope this helps Hanns Per

[vertew]

Ok, thanks for that Hanns ... roller bearings now ordered  *smile*

[Hanns Per]

just talked to Kolben Dümpert and they confirmed they do not have manufacturers reference numbers, they only sell after dimensions. If You intend to contact Dümpert here is my invoice number and date 210318 dated 08.02.2021 which You can use as reference.

[vertew]

Thanks again Hanns, I'll send you a PM as I've some other questions.