Dogbytes' R80 ST project

[desmo2]

Not as much of a pain doing it as it is getting them in the correct place . I wasted my first frame by getting this wrong . All sorted now though .... but then anybody can get it right second time !

 

[Rob Farmer]

I can't help but wonder if you guys are some kind of off road riding gods to need all these frame mods. This fellow did the Paris Dakar on an R65 with his only mod being a windshield

 

[desmo2]

Did he win ?

 

[Dogbytes]

I can't help but wonder if you guys are some kind of off road riding gods to need all these frame mods. This fellow did the Paris Dakar on an R65 with his only mod being a windshield

Oh I don't need them, I just like doing them - that's why I take my time and savour the process!

 

[Dogbytes]

oh yeah so you say but if you'd really done it there'd be pictures?

I would attach one but I don't think I can - i haven't renewed my subscription yet! I'll email it to you...

 

[Kenny]

Did he win ?

He hasn't quite finished the race yet !

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Update please ... I need inspiration

 

[Dogbytes]

He hasn't quite finished the race yet !

+++++++++++++++++++++++++++++++++++

Update please ... I need inspiration

Will upload some pics today. I've been doing some work on it and I've renewed my subscription!

 

[Dogbytes]

A little more progress...

A bit of work on the 'real' driveshaft spacer - the dummy one for positioning purposes was aluminium, this one is stainless. Stripping the engine to make it lighter to ease moving it around in the frame whilst drilling the frame for the new rear engine mounts. Do I really need those bits? Making it lighter still!

I will have some original bits for sale - exhaust, oh all kinds of stuff!

 

[Dogbytes]

Still at it...

In order of appearance:

1. That's about where the motor needs to be.
2. Marking the tubes for drilling - not central, Sod's law being what it is!
3. Thus is going to be a pig.
4. But we got there.
5. Looks about right!

The rear mounts are now tacked in but I've run out of Argon for the TIG and I need to scrounge a lift to the suppliers. That'll be a job for tomorrow. After that I'll fit the diagonal (steering head - swing-arm pivot) tubes and then the removable frame rails. Oh yeah, and the fairing mounts... and the new rear subframe...

I've been thinking of making my own sump extension/external oil filter conversion. I know you can buy them - but where's the fun in that!

 

[Kenny]

Proper airhead engineering

 

[mavis cruet]

aah. i like the idea of a raised engine, more ground clearence and looks cool. if you go for the dry sump does that mean you can remove the sump, giving even more clearence? whats with moving the engine forward? have i missed summat? at the risc of sounding patronizing, have you checked the front wheel wont hit the engine? keep it going, this ones fun to watch!!!!!

 

[desmo2]

Here's mine . My rear mounts are central , and as you can see , are brazed in

 

[Dogbytes]

Here's mine . The rear mounts are central , why aren't yours ? As you can see , the mounts are brazed in , of course

I think my front ones are higher and possibly further forward. That has an effect on where the gearbox output ends up in relation to the driveshaft.

 

[Dogbytes]

aah. i like the idea of a raised engine, more ground clearence and looks cool. if you go for the dry sump does that mean you can remove the sump, giving even more clearence? whats with moving the engine forward? have i missed summat? at the risc of sounding patronizing, have you checked the front wheel wont hit the engine? keep it going, this ones fun to watch!!!!!

I really have no idea where the sump will end up! That is, there are a couple of options - dry sump or not and then there's the increased-capacity spacer with external oil filter option that I fancy doing too

PS No, the front wheel won't hit the motor. Well, not unless I hit something else first!

 

[Dogbytes]

Proper airhead engineering

There's probably a German or two that'd have an opinion on that!

 

[desmo2]

I think my front ones are higher and possibly further forward. That has an effect on where the gearbox output ends up in relation to the driveshaft.

I've got a pretty steep swingarm angle which could explain it ?

 

[Dogbytes]

If I was doing it again I'd do it slightly differently - and probably end up with the rear mounts even higher. However I don't think it'll make any difference in practice... much like the rest of the mods

 

[Dogbytes]

Just posted this on 'For Sale' if anyone's interested

Touratech Hard Part for R1150 GS.

I bought it when I bought my 1150 - back in 2000 - and I never got around to fitting it. Are you seeing a pattern forming here?

Anyway I just found it again and if anyone wants it it's yours for £50 inc. P&P

 

[SeanW]

swingarm travel?

I'm no engineer, but have an engineering question...

it looks like the drive shaft is going to be parallel relative to the gearbox output shaft only when the rear is completely unloaded (as it is on the pics).

But when the shock is supporting the bike's weight and a rider's, the shaft is going to end up deflected upwards quite a bit at the gearbox end

Isn't this going to mean that at maximum shock compression the drive shaft ujs will be under much more stress that they will be at maximum extension? Wouldn't it be better for the shaft to aim to have it more or less parallel to the output shaft when under standard load?

I've never looked at this angle on my airheads, but I suppose my expectation would be that if the bike was on a stand with both wheels off the ground, I'd expect to see the swingarm /drive shaft deflected below a line going straight out along the line of the output shaft, not parallel with it. Maybe this is just my imagination.

Or maybe you're gonna fit a longer shock?

 

[Dogbytes]

I'm no engineer, but have an engineering question...

it looks like the drive shaft is going to be parallel relative to the gearbox output shaft only when the rear is completely unloaded (as it is on the pics).

But when the shock is supporting the bike's weight and a rider's, the shaft is going to end up deflected upwards quite a bit at the gearbox end

Isn't this going to mean that at maximum shock compression the drive shaft ujs will be under much more stress that they will be at maximum extension? Wouldn't it be better for the shaft to aim to have it more or less parallel to the output shaft when under standard load?

I've never looked at this angle on my airheads, but I suppose my expectation would be that if the bike was on a stand with both wheels off the ground, I'd expect to see the swingarm /drive shaft deflected below a line going straight out along the line of the output shaft, not parallel with it. Maybe this is just my imagination.

Or maybe you're gonna fit a longer shock?

That is absolutely right and is why I'd do it differently next time

That said, there is enough safe angle of movement there to give about 120mm of wheel travel before anything approaches critical - even with the standard length shock fitted and a longer one is planned. As a track bike this will have significantly less static sag than a paris-Dakar replica so I don't think there's a problem.