BGM rear shock ~ rebuildable ?

[byron]

I thought that my Special was feeling a little bouncy, and there was oil over the rear of the engine...
yep, my BGM rear shock has lost all the oil and now has no damping....
it has done over 14000 miles, so it's not like it's failed on the first ride.
but are these serviceable ?
or would the cost not be too far off getting another decent rear shock...?
thanks

[dickie]

Any number of people in the UK will rebuild
non-rebuildable shocks.

I've had good service from Maxton and mct. There are numerous other ones though. Several seem to be clustered around Huddersfield like fox racing. These are all focused on 'proper' bikes, but a damper with a spring wrapped around it is a damper with a spring wrapped around it.

Mct might suit you as they are based in Stowmarket.

[byron]

thank you.
will give mct a look

[Leotech]

My day job is servicing shocks and forks for off road competition motorcycles. Recently a friend gave me an old Taffspeed unit that had developed a leak.

I got it in pieces as it is rebuildable but it used a strange type of seal, Taffspeed said they didn't sell service kits for them and I have been struggling to locate a seal through my network of contacts. I am currently looking into he feasibility of making a new seal head and using a more common seal.


With the BGM unit being more current it may use a more readily available seal. They may even offer a service kit, is it gas pressurised?

[Warkton Tornado No.1]

Post by Leotech » Mon Aug 01, 2016 10:37 pm

My day job is servicing shocks and forks for off road competition motorcycles. Recently a friend gave me an old Taffspeed unit that had developed a leak.

I got it in pieces as it is rebuildable but it used a strange type of seal, Taffspeed said they didn't sell service kits for them and I have been struggling to locate a seal through my network of contacts. I am currently looking into he feasibility of making a new seal head and using a more common seal.


With the BGM unit being more current it may use a more readily available seal. They may even offer a service kit, is it gas pressurised?

I’m watching this Post with interest as I too have a BGM rear shock absorber that I suspect may need checking out as I think the seal(s) may be leaking.

I believe that they only use oil (not gas pressurised).

I also have a GAZ rear shock absorber that I suspect is in a similar state.

Finding any information about either is proving fruitless. Both units must be serviceable, but I guess that neither manufacturer wants to make it easy for anybody proficient enough to do so....

[Toddy]

Would it not be worthwhile contacting Scooter Center or an English BGM Dealer to see if there is a service kit or if they are repairable ?

[Digger]

I thought Mark was a BGM dealer.

[Leotech]

Post by Leotech » Mon Aug 01, 2016 10:37 pm

My day job is servicing shocks and forks for off road competition motorcycles. Recently a friend gave me an old Taffspeed unit that had developed a leak.

I got it in pieces as it is rebuildable but it used a strange type of seal, Taffspeed said they didn't sell service kits for them and I have been struggling to locate a seal through my network of contacts. I am currently looking into he feasibility of making a new seal head and using a more common seal.


With the BGM unit being more current it may use a more readily available seal. They may even offer a service kit, is it gas pressurised?

I’m watching this Post with interest as I too have a BGM rear shock absorber that I suspect may need checking out as I think the seal(s) may be leaking.

I believe that they only use oil (not gas pressurised).

I also have a GAZ rear shock absorber that I suspect is in a similar state.

Finding any information about either is proving fruitless. Both units must be serviceable, but I guess that neither manufacturer wants to make it easy for anybody proficient enough to do so....

If you remove the spring it will become apparent if the oil has leaked.

Im in a similar position with the Taffspeed unit. The seals won't have been manufactured exclusively for them but its finding who made them. Taffspeed just said the manufacturer had gone but Im guessing the manufacturere will have bought the seals in for the shocks and not made them in house. Its a shame a good product is deemed useless for the want of a ten pound piece of rubber.

[HxPaul]

Lots of different shapes and sizes of oil seals.
https://www.google.co.uk/search?q=sizes ... E_rn5eM%3A

[Warkton Tornado No.1]

Post by Leotech » Tue Aug 02, 2016 9:15 am

If you remove the spring it will become apparent if the oil has leaked.

Im in a similar position with the Taffspeed unit. The seals won't have been manufactured exclusively for them but its finding who made them. Taffspeed just said the manufacturer had gone but Im guessing the manufacturere will have bought the seals in for the shocks and not made them in house. Its a shame a good product is deemed useless for the want of a ten pound piece of rubber.

Post by HxPaul » Tue Aug 02, 2016 10:28 am

Lots of different shapes and sizes of oil seals.
https://www.google.co.uk/search?q=sizes ... E_rn5eM%3A

This Post has probably struck a chord with a few of us on the Forum because by our nature of wanting to maintain & modify our quirky Italian shopping machines, we tend to try & want to ‘demystify’ most of what is involved in the whole machine.

So, the sensible remarks so far, along with the technical information, are encouraging.

However, despite my belief that most competent owners could probably tackle a shock absorber rebuild, it’s encouraging that ‘we’ have somebody on board that has a day job doing precisely just that.

What’s stopping me for the moment is my preference in having the new components to hand that will be required in the rebuild.

That’s the sensible approach, surely?

The alternative would be a preference to save a few quid of the likely £100+ ‘professional rebuild’ costs & sub the job to a fellow enthusiast that just happens to be in the appropriate industry.......

[byron]

thanks. interesting replies.
happy to let my BGM shock be dismantled to see how serviceable they are; if you fancied another one in bits on your bench Leotech..?
[they do damp with just oil, not gas]

[Leotech]

thanks. interesting replies.
happy to let my BGM shock be dismantled to see how serviceable they are; if you fancied another one in bits on your bench Leotech..?
[they do damp with just oil, not gas]

What has MB said?

Im away tomorrow until Monday at a British Championship race on the Isle of Man. I'd be happy to have a look at one but the bike work has to come first.

Having just looked at the BGM shock on a photo I would say it is rebuildable and serviceable providing the seals etc are obtainable.


Ive made a few more enquiries about the Taffy seal today but not had any luck as yet. i'm 90% tempted to modify it and get a easily available seal.

[Leotech]

The Taffspeed shock I had that was leaking, I've managed to source some seals to repair it.

It just needs tested now to see if it will not leak! The only seal I could get wasn't exactly as the original so thats why it needs road tested.

[Warkton Tornado No.1]

Re: BGM rear shock ~ rebuildable ?
Post by Leotech » Wed Aug 17, 2016 4:29 pm

The Taffspeed shock I had that was leaking, I've managed to source some seals to repair it.

It just needs tested now to see if it will not leak! The only seal I could get wasn't exactly as the original so thats why it needs road tested.

I hope it works out.

Any attempt is a positive step IMHO.

I looked into serviceability/seal replacements for the GAZ shocks we have but didn’t get too far, so if you can shed any light on those, it would be appreciated, as would whatever can be done for the BGM units....

[Leotech]

The only real way is to strip one and have a look see.

I'm going to fit the Taffy one and have a ride at weekend.. See how it goes.

[HxPaul]

I once had a hydrailic inboard front disc and the seals had become hard and started to leak.I searched everywhere for new seals to no avail,a friend of mine suggested trying rubber o rings,with nothing to loose (except possibly my life) I sourced some o rings and they worked perfectly never leaking and the brake was good.

[byron]

The Taffspeed shock I had that was leaking, I've managed to source some seals to repair it.

good work.
fancy trying a BGM one next...?

[Warkton Tornado No.1]

Unread postby HxPaul » Fri Aug 19, 2016 7:17 pm

I once had a hydrailic inboard front disc and the seals had become hard and started to leak.I searched everywhere for new seals to no avail,a friend of mine suggested trying rubber o rings,with nothing to loose (except possibly my life) I sourced some o rings and they worked perfectly never leaking and the brake was good.

'O' rings will work safely but the special section seals will work better because they are designed to distort so that the piston retracts a little once the pressure is off.

Dave Webster may have been a pedantic character, but he knew what he was on about by advocating the use of the correct seals in his brake conversions.

I've known people buy 'o' ring versions & ditch them due to brake drag.

[HxPaul]

Its possible that after some use the brake did drag because shortly after fitting the o rings and making sure the brake worked ok,I sold the scooter.

[Storkfoot]

....but the special section seals will work better because they are designed to distort so that the piston retracts a little once the pressure is off.

Dave Webster may have been a pedantic character, but he knew what he was on about by advocating the use of the correct seals in his brake conversions..

I am interested in this. I have recently suffered a binding inboard hydraulic. I have just replaced the seal ( they are a Kawasaki part number) but I can't test it until I get the hub back from paint (DOT 4 does make a mess).

When I took the old seal out I was hoping there would be some visible signs of degradation but there were none. The new one did "feel" more springy rubber though.

Anyway, sorry for the thread drift but that's useful to know WT