Which ehngine bars or cylinder head protection?

[haditlowered]

The pegs were not grounded when i was T-Boned on a roundabout, but the pegs did pick up a bit of grass when i ditched it in Dent last year - i cant say enough both these bars - i dragged the bike our of the ditch and across the tarmac on these bars, the handlebars and foot pegs were clear of the ground, i also have a rear drive protector fitted that and the bars took the brunt of the fall - they are superb.

 

[haditlowered]

Solid but do they touch down before the footrests?

Cornering - the pegs touch down before the bars - not quite had the bars down yet - but now i have my TCK 70's fitted.... it's a matter of time.

 

[RSavage]

Ive been surprised how close the head gets on tight right handers. Not that I look very often but when I have sneaked a peek...

Know what you mean. Now that I have the LC adjustable footpegs I find it disconcerting how easy it is for my toes to touch down. First time was an 'experience' and I have sneeked a glance down there a few times but doing so is inclined to induce target fixation

 

[RSavage]

The pegs were not grounded when i was T-Boned on a roundabout, but the pegs did pick up a bit of grass when i ditched it in Dent last year - i cant say enough both these bars - i dragged the bike our of the ditch and across the tarmac on these bars, the handlebars and foot pegs were clear of the ground, i also have a rear drive protector fitted that and the bars took the brunt of the fall - they are superb.

What about damage to the underlying structure of the bike? The fears that Bendy Toy and I have concern directing the full force of a drop onto the block/sump/frame.


And how difficult is it to remove them for valve adjustment? I'd be concerned about the effects of repeatedly removing bolts secured into alloy with Loctite.

Richard

 

[Bendy toy]

The additional mounts can only be good for distributing crash forces but as Rich says the crash bars have to be bigger stress raisers on the engine cases than the cylinders themselves would be.

The front lower crash bar mounts onto what's effectively the sump pan so it wont have the strength of an end plate or cylinder attachment. The rear crash bar mounts at the rear subframe mounts. But again the are on the sump pan. They seem to be build for push pull loads along the length of the bike. There does not seem to be much strength to take a side impact force.

This could all be over analysing the issues but crash bars are not low cost. After my crash on a rough road covered in mud I began thinking about what I really need, I realised the cylinders are about as strong as it gets and more than up to the task of protecting the bike. They do need abrasion protection of course. However I believe the available crash bar cages are fixed to parts of the bike with questionable side impact strength. They risk huge cost if the engine cases can't take the loads.

Simple option is the Machine Art X-Head (polypropylene I believe) and remove the crash bars. If you have a GSA the OEM bars will need some mods to bring them behind the head line. Even these are not perfect because they use the standard M6 screws mounts into the actual cylinder head. Shear these lugs away and the head is scrap. They will also look pants after the first car park tumble.

Another lower costs option (maybe) is Nylon or Delrin pads screwed to the rocker covers. These would be bolted in place so the covers would have to be drilled and the bolt heads would need to be recessed like any other crash bung idea. They would take abrasion without looking crap afterwards.

The normal drum shape bungs are probably not suitable as they are quite tall and likely to get ripped off the cover. But it's not really rocket science to come up with something suitable.

I have a crash bung on the paralever pivot point. It got chamfered a little when I had my falling off on slippery salt but its still 100% serviceable and did a great job to protect the FD case. https://www.motorcycleparts-hornig....html?utm_source=googlebase&utm_medium=organic

 

[haditlowered]

The AltRider bars fit to the same locations as the frame mountings on the bike, they is the strongest points, there is a detailed description on the AltRider web site with images, it's true that the bars take a beating in a spill, but you can polish out the bars a lot easier than head guards, and living with scratched bars is not as bad as damaged head guards aesthetically. the X Art are £120 a pair and "one use only", bars will take a lot more knocks - mine have had two already and being good quality are still looking good.

 

[Bendy toy]

The front crash bar mount is 1/3 of the way along the engine case front. The back mount is 1/3 from the back end so neither is close to the strong end plates. The lower frame mounts are not built to take large side forces and while they will be stronger than the front crash frame points they don't need huge lateral strength. In comparison to the cylinder head mounted crash bungs on a sports bike the BMW crash bar mounts are weak to say the least.

Agreed the X-heads are single use or could say sacrificial. But additional alloy plates on the X-Heads will take the car park tables and low speed scrapes. Easily and cheaply replaced. In a full on crash the sacrificial effect of the X-heads will be well worth the cost.

 

[haditlowered]

The upper mounts on the Altrider bars are fitted to the long "thru bolt" at the top of the engine, so any impact is transferred through the bolt, rather than impacting on the engine itself, in addition to that, the front cross bar that passes in front of the engine also takes the impact forces, the lower rear fixing uses the tubular frame mounts, so the side impact forces are taken by the frame and not just the sump casing, i don't think they use the same fixing points that BMW do. Whichever you choose - bars or engine casings i think it's a wise investment.

 

[Bendy toy]

The magnesium covers are brittle so the bike certainly needs some sort of protection. A good thump onto a lumpy stone or kerb (as I did) will easily crack a rocker cover.

The X-Heads will quickly look rough after even a driveway tumble so I plan to make some 2mm alloy plates to take the cosmetic damage. But they need to be curved to fit so could be "fun".

 

[RSavage]

The magnesium covers are brittle so the bike certainly needs some sort of protection. A good thump onto a lumpy stone or kerb (as I did) will easily crack a rocker cover.

The X-Heads will quickly look rough after even a driveway tumble so I plan to make some 2mm alloy plates to take the cosmetic damage. But they need to be curved to fit so could be "fun".

Leather bag filled with sand, wooden bats and a great deal of patience should have you producing beautifully curved objects in, oh I don't know, about 20 years if you work hard at it ;-)

 

[Bendy toy]

Leather bag filled with sand, wooden bats and a great deal of patience should have you producing beautifully curved objects in, oh I don't know, about 20 years if you work hard at it ;-)

I had a suspicion there might just be the odd snag in the plan.

 

[RSavage]

I had a suspicion there might just be the odd snag in the plan.

Heh heh heh

Funnily enough, I used a bag of builders (builder's ?) sand as a base and a crudely shaped bit of wood to tap the dent out of my rocker-cover cover. It's not great but I didn't add any dents doing so.

Off to Wales now for the WNR.

R

 

[Bendy toy]

Ive done the sand filled leather bag thing but (very) not recently. I may well give it a try as I'm well off for 2mm aluminium and it's a minimal curve.