I've been looking at how to carry camping gear etc for a forthcoming trip and have made a frame to keep throwover luggage stable, but I think there's a weak spot in the frame - on the left hand side at the back of the seat where the removable strut is, the horizontal top frame has no triangulation to prevent flexing if there's a lot of weight on the rear rack. The right hand side has a gusset welded in.
So the question is, does anyone heavily load their ttr while on rough road excursions and has anyone suffered frame cracks behind the removable strut top-mounting point? I have no idea how thick the frame tube is up there, but extra bracing will be complicated to do neatly.
@ttiranlp: If you're reading - I know your bike has done some miles well loaded! How does the frame look back there?
I have seen an extra reinforcement bar being put in on the left side. I'm fairly sure Lois Pryce's ttr had an extra tube welded in from the footpeg to the rear frame... been trying to find a picture of it somewhere...
You may be right to be worried Simon. On the last A2E we had to take some time out to weld up a certain TTR owners rear subframe. The photos below show exactly where the fractures occurred and, no, he didn't have a rack fitted.
Simple enough to fit a length of tight fitting tube inside to add some strength and get the correct shape/bend and MIG it all up - no trouble since
Pic number 1 is the exact spot I was thinking of Brian. Although the steel looks like it has thinned a bit, it is an obvious flex node. The engine cradle one I've seen before although I can't really see why it's so common unless the welding jig introduces some stress during manufacture. Pic 4 almost looks like the weld has weakened the tube next to it! I think I might just beef up the rack a bit to ease the strain rather than modify the chassis.
Thanks Malcolm. Yes, all my own work! The top rack stays on permanently and doubles as grab handles. The sides unbolt when I don't need them. Originally designed to hold a pair of Altura Arran cycle paniers, but I lost confidence in the plastic mountings and now have some larger throwovers for the next adventure.
The tyres are Heidenau k60 s. They're a similar pattern to Mefo Explorers I believe, and work really well on all surfaces except deep mud - they don't really dig well, although better than a lot of people expect! Designed as an "adventure bike tyre" (awful name) but they're tough and long lasting and grip to cold wet tarmac like a proper road tyre, and to rock almost like a trials tyre. I love them, but tend to use Mitas 644 army specials for green laning in the uk as we encounter mud, and hard slippery clay more where I tend to ride. The front tyre is quite a rounded profile with not enough sidelug for confidence in ruts. They were on the bike for the VINCE event in Spain, for which they are perfect.
Rack now has a bit more reinforcing which may have spoilt the "line" a bit, but will be hidden by the panniers anyway. Photos will hopefully follow when I'm back home in December...
Oooh!! That's even better! I've recently just put a new K60 on the front and am loving it! The rear is getting changed when funds allow. I've heard they're excellent tyres and last for ages too! It's been pretty wet and miserable recently, but the tyres are handling great! So I've got some confidence in them.
Now put some extra bracing in and had it powder coated...
And a heat shield...
With Andy Strapz panniers...
Those with eagle eyes will spot the different tank/seat. I prefer the OE setup for looks and ergonomics off tarmac, but really need the extra range sometimes. Decisions decisions...
I'm afraid I can't see much of an advantage in adding extra straps to which you attach your own straps. Am I missing something? Just means more straps and you still need something solid underneath to take the weight/keep things away from exhaust/wheel etc.
Thanks Howard,
I don't think your's will affect fuel economy unless you're planning to ride sideways? Frontal area is slimmer than mine. Nicely braced too. I think people often forget that the loading is inward rather than straight down on a bouncing bike.
I'm fortunate to live on a farm with a well equipped workshop. My rack is made from solid 10mm bar, bent with a combination of oxyacetylene heat, formers made from bits of appropriate diameter tube, hammers and patience! Arc welded. Bending tube to those tight radii is beyond me and the tools I have to hand, but I think although it's slightly heavier, the solid bar is easier to straighten and repair in the event of ground contact.
That exhaust of your's looks loud! Watch that the gasses exit past the back of your panniers - it gets pretty hot back there!
Have you got a trip planned?
Ride safe,
Simon.
Well, I was referring to the weight of mine as I used 25x5mm flat bar. Probably weighs the best part of 6 Kg, and supposedly the frame is only rated to carry 90Kg so with a rider of 70Kg that only leaves 15Kg for luggage! I made a brace for the LHS of the rear frame today that runs from the helmet lock to the flat bracket that the little flappy chain guard is bolted to. Only a bit of 18 G steel tube with flattened ends, but it completes the triangle should offer some additional support.
Sounds like a a handy place to be with all that equipment. I hope to have my very own man shack one day, but for now, the car club at the place I work is where I carry out all my fettling. Still, I've done OK with a vice, Gabro sheet metal brake, hydraulic press and a MIG welder. Oh and a sewing machine in the bedroom/at the girlfriends (for the home made panniers).
I've been painstakingly restoring a 1984 XT600 for the past 11 months in that car club with a view to travelling to Mongolia and back on it, and I'm almost done. The TTR is actually my partners bike who will be travelling with me, but thankfully Brian had already done a good job on the TTR in Oct 2014, so I've not had to worry about on her (she's named Gertrude after Gertrude Bell) apart from a fork rebuild, exhaust shims and trouble shooting the carburettor. Turns out the choke plunger's O-ring had come off and stuck in the end of the choke bore, and was causing a very rich mixture! Nothing a sheet of silicone and a scalpel couldn't sort.
Apart from heated grips and some wide foot pegs which need fitting, she's ready to journey Central Asia!
Ta for the note about the exhaust. I shall improvise a heat shield! And yes, it is loud. Too loud. It's a Supertrapp E.A.R exhaust if you're interested. Nice sound, but maybe not for 10K miles....