Dogbytes' R80 ST project
- Thread starter Dogbytes
- Start date
desmo2
Registered user
Hi , I've been following your thread and am doing an off road BM with lifted engine etc too .
I have to comment on your latest bracing tho' . My main interest is pre '65 scrambles and as such would advise that Metisse scrambles frames have a similar headstock layout and bracing of this nature must never be done . As advised by Rickman . Not too sure why but seem to remember flexibility being mentioned ? However , keep up the good work , I'm enjoying following it .
I have to comment on your latest bracing tho' . My main interest is pre '65 scrambles and as such would advise that Metisse scrambles frames have a similar headstock layout and bracing of this nature must never be done . As advised by Rickman . Not too sure why but seem to remember flexibility being mentioned ? However , keep up the good work , I'm enjoying following it .
fayeslane
Registered user
Just been in the shed welding then looked at your pics..................weld must behave differently in the southern hemisphere
I'm sure that that's a valid point for an off-road frame. I had originally fitted the HPN-style headstock bracing but, try as I might, I couldn't figure out what it was doing so this week I took it off. However this isn't an off-road frame (at least not that kind of off-road) and what I want is torsional strength and I think that this will contribute.
In reality it's all a bit academic. It will only ever be my toy and, as such, is unlikely to be ridden to its limits. I'm doing it because I can, because I enjoy it, as an example of what can be done with these frames and because others too like to look at interesting mods on bikes in general.
Just been in the shed welding then looked at your pics..................weld must behave differently in the southern hemisphere
I have had a few problems welding this frame and I think I got to the bottom of it only yesterday, although I still have to research it further. In terms of mild steel TIG rods, I have two types - 2.4mm A75 rods and 1.6mm A15 rods. When using the A75 rods they'll flow nicely and then explode into a spitting mess for no apparent reason whereas the A15 rods seem to flow much better. I don't know why but there may be an expert reading this who can enlighten us.
Frames are a pain to weld because access isn't always great. I use a water-cooled torch because its smaller and I take everything I can off the frame, so that I can get it on the bench in the best position to get to the bit I need to weld.
I know people who weld far better than I do but skills are like tools and you can only work with what you have. The main thing is that it's sound. As a friend of mine, who is the best welder I've ever met, says - The best welds aren't always the prettiest and he prettiest welds aren't always the strongest.
I'm sure that that's a valid point for an off-road frame. I had originally fitted the HPN-style headstock bracing but, try as I might, I couldn't figure out what it was doing so this week I took it off. However this isn't an off-road frame (at least not that kind of off-road) and what I want is torsional strength and I think that this will contribute.
In reality it's all a bit academic. It will only ever be my toy and, as such, is unlikely to be ridden to its limits. I'm doing it because I can, because I enjoy it, as an example of what can be done with these frames and because others too like to look at interesting mods on bikes in general.
For that sir, I applaud you
I couldn't make you more right!
fayeslane
Registered user
Mine look like cocky shit & have a similar strength
I'm sure you're being excessively modest.
Frame's done!
After something like 80 hours of work, the frame is, at last, finished. I'll chuck some paint over it over the next few days and then post some pics.
Seat subframe, recon forks and fit emulators, make some fairing brackets and make the rear-sets next...
After something like 80 hours of work, the frame is, at last, finished. I'll chuck some paint over it over the next few days and then post some pics.
Seat subframe, recon forks and fit emulators, make some fairing brackets and make the rear-sets next...
ive just brought two welders ,and id be more than happy to be able to weld as good that
ive just brought two welders ,and id be more than happy to be able to weld as good that
Cheers
I've certainly got a bit better at welding in awkward positions over the course of this project!
Db, can you show me a pick of your front tank mount please...providing you are using the standard tank mount behind the headstock....?
T.
T.
I'll put a pic up tomorrow morning. I'm using the standard tank mount.
As requested...
Attachments
Are you not going to put a gusset in there?
Something along the lines of these maybe?
I have just done this to a frame but I am wondering how the standard tank needs to be altered to fit....
Crazyivan in Belgium has sent me another pic showing how HPN cut/alter the front bracket on the tank to fit over the headstock gusset and repostioned tube shown on the first pic above.
Something along the lines of these maybe?
I have just done this to a frame but I am wondering how the standard tank needs to be altered to fit....
Crazyivan in Belgium has sent me another pic showing how HPN cut/alter the front bracket on the tank to fit over the headstock gusset and repostioned tube shown on the first pic above.
Are you not going to put a gusset in there?
Something along the lines of these maybe?
I have just done this to a frame but I am wondering how the standard tank needs to be altered to fit....
Crazyivan in Belgium has sent me another pic showing how HPN cut/alter the front bracket on the tank to fit over the headstock gusset and repostioned tube shown on the first pic above.
I did similar but a little simpler mod to Pete Keys' frame and he ended up cutting some of it away to clear his tank. I think the angles were different though. The one you posted looks like a standard tank might fit. I did mine the same as I did Pete's and then, last week, decided it wasn't going to achieve what I wanted it to and took it off. Basically I don't need it to withstand a high speed landing off the top of a sand dune but I do need the steering head axis to remain constant in relation to the swing-arm axis - so I did this instead.
Attachments
The headstock flexing backwards is the issue that the gussets prevent, and any increase in front suspension ability then this is critical. And with 48mm WP USD forks to fit, I had no choice, I have gone down the route of the blue framed pic.
So, cutting the tank/bracket and reinstating the mounting tube on the frame slightly higher is on the cards.
Of course, using the larger tanks I could of avoided this as the mounts are on the down-tubes heading under the engine, but oh-no, this bike's having a standard GS tank!
The second frame I'm doing here is going to have a special tank.....if it ever arrives from Italy!
So, cutting the tank/bracket and reinstating the mounting tube on the frame slightly higher is on the cards.
Of course, using the larger tanks I could of avoided this as the mounts are on the down-tubes heading under the engine, but oh-no, this bike's having a standard GS tank!
The second frame I'm doing here is going to have a special tank.....if it ever arrives from Italy!
Paul Rochdale
Registered user
Because the gusset on the blue frame restricts fitting of a standard tank I approached it from a different direction. A short length of 1"x1" mild steel tube going from the bottom of the headstock to the horizontal tube at the top of the frame. Tank fitting won't be affected.
I'll add a pic when the frame returns from the Dartford powdercoaters.
I'll add a pic when the frame returns from the Dartford powdercoaters.
Canuck
Registered user
The second frame I'm doing here is going to have a special tank.....if it ever arrives from Italy!
You're not going for one of those TAG tanks are you? In kevlar or fiberglass?
Personally, I'd quite like a replica, black and silver R90S tank. In carbon fibre, with the weave showing in the black areas. Oh and it would have to cost under fifty quid too...
