Rear drum brakes

[Nbowe]

Just fitted a rear hub from my Indian gp150 to a new sil gp200 but when I tighten it up brakes are fully on,locked up solid.
Tried changing to my original shoes from the GP150 but they are worse.i,m a bit puzzled,thought the hub was universal.Any ideas fellas.cheers

[Warkton Tornado No.1]

I would measure the lining diameter where the shoes operate on of both hubs. However, they are unlikely to be much different. It’s just a check.

Then compare both to see where else the problem might be, such as the area around the cone or anywhere there may be evidence of there being a difference.

[HxPaul]

Have you disconnected the cable from the brake operating arm ?

[Nbowe]

I'll do some measuring tonight,the brake cable is disconnected.The hub is off my gp150 engine and worked fine.I even tried
the old shoes from the gp150 on the gp200 engine but the hub still locks up on tightening so the problem must be with set up of the gp200 engine??????

cheers for your suggestions fellas

[dickie]

do you know if it's the friction material locking against the braking surface of the drum or the sides of the shoes contacting the inner face which is vertical to the road?

if that make sense.

[Nbowe]

yeh that makes perfect sense dickie but I'm not sure will have to have another look tonight and do some measuring.I couldnt see any tell tale marks to suggest its the side of the shoes that are catching but I think that may be the case as it gets worse as you tighten the hub.I'll let you know how I get on

[Nbowe]

I've measured every damn thing on both 150 and 200 engines and they appear to be identical.the only way I could solve the problem is to use the slightly worn shoes off my gp150 and remove the metal feet from the ends of the shoes the drum now turns freely and the brake works fine.one thing I didn't measure was the distance between the pivot pins the shoes locate on.wonder if they're further apart.I will check that next time the hub comes off(which will probably be quite soon).cheers for all the help

[Triffid]

Check your pivot points - I seem to remember some information regarding incorrect positioning of the pivot point including the brake operating arm on some SIL engines - especially those made after mainstream production of the Vijay had stopped.

[peejay]

Check your pivot points - I seem to remember some information regarding incorrect positioning of the pivot point including the brake operating arm on some SIL engines - especially those made after mainstream production of the Vijay had stopped.

this rings a bell with me as well

[drivera]

Might be way off the mark but are the brake cams on both engines the same , why not try the one from your GP150 in the 200 and see if they shoes are ok then ?

[Warkton Tornado No.1]

If you've got any cam other than GP, then that would explain it . GP is a lot thinner, face to face.

[Nbowe]

Have measured both cams and they are identical.I think the pivot points may be the problem.I,ll run it for now and see how it goes.cheers fellas

[Digger]

The dodgy pivot Indian cases normally result in the shoes not centring on the hub braking surface rendering the brake almost useless - you seem to have the opposite problem.

[jonw]

Li cams in both but the 200 has Li shoes and the 150 has GP shoes?

[Warkton Tornado No.1]

The Indian crankcases are renowned for being out in their positioning of the brake pivot centres.

In the worst cases, I have re-drilled where the hole should be (eccentrically to the existing hole) oversize to suit an M8 helicoil & fitted it.

I accept that this solution is extreme & have engineered another solution, but although I have generated a 3D model, I have not yet obtained quotes.

BTW. I am aware of the other solutions offered by Jockey Boxenstop but mine continues to use standard generic Innocenti based brake shoes.

I’m sorry that doesn’t offer an immediate solution but it would be useful to be aware of the extent of the problem prior to a decision to commit further.

[Nbowe]

Thanks for the info

[gaz_powell]

"I accept that this solution is extreme & have engineered another solution, but although I have generated a 3D model, I have not yet obtained quotes".

Interesting !!!!

Any prototype ?

[Nbowe]

Just an update.the jockey boxenstop kit did not solve my problem.fitted the kit and hub which turns freely but full adjustment gave me no brake at all.ive got an Indian hub in the shed which I will try.let you know how I get on

[maz]

Have you shimmed the cone / hub from the bearing.............. this has the effect of pushing the hub out from the caseing and possibly better sighting the shoe material on the centre of the drum/breaking ring

I've had a situation , using an ' Indian ' hub, where the shoes were rubbing on the centre face of the hub.