Carrying on with the shimming calculations...
Shift drum. In the photos it was obvious that the calipers were at an angle - I couldn't measure straight due to different diameters on the ends of interest.
Trigonometry: End 1 has a 45mm diameter, end 2 has a 32mm diameter, I measured 88.13mm length between end contact faces. The 88.13 will be the hypotenuse of a right angled triangle, with (45 - 32) / 2 = 6.5mm, the short side. I want the length along the axis of the drum.
Sqrt (88.13^2 - 6.5^2) = 87.89 mm true length.
Left side of crankcase: 55.38 - 25.10 = 30.28 mm depth
Right side of crankcase: 85.22 - 25.10 = 60.12 mm depth
Gasket thickness (via micrometer) was 0.35 mm.
Prescribed endfloat (via Haynes manual) is 0.25 mm.
Shim gap = LH depth + gasket + RH depth - specified end play - drum length, so
Shim gap = 30.28 + 0.35 + 60.12 - 0.25 - 87.89 = 2.61 mm (total shim thickness)
For the record, I found I had nearly a millimeter of end play on reassembly. The current shims are nowhere near the right size.
The Haynes manual gives the following procedure for working out the RH shim thickness:
RH depth - 59.0 mm - 0.125 mm (half endfloat) = RH shim
so 60.12 - 59 - 0.125 = 0.995 mm (realistically, 1.00 mm)
So LH shim has to be 1.61 mm.
Input shaft.
The procedure here is to pull the bearing cap off the end of the shaft assembly, fit it to the bearing in the case, and measure depth to the flat face of bearing cup. The shim actually sits on the assembly main shaft behind the bearing cup.
Very similar to before:
Left hand crankcase depth = 79.06 - 25.14 = 53.92 mm
Gasket: 0.35 mm
Right hand crankcase depth = 90.48 - 25.14 = 65.34 mm
Input shaft length = 116.16 mm
Allowable end play = 0.15 mm
Total shim size required = 53.92 + 0.35 + 65.34 - 116.16 - 0.15 = 3.30 mm.
As with the shift drum, to centralise the shaft in the cases, a fixed figure (this time it's 64mm) is taken off the RH depth, together with half the end play.
RH shim = 65.34 - 64.00 - 0.075 = 1.265 mm
LH shim = 3.30 - 1.265 = 2.035 mm.
Output shaft.
As for input, really.
LH crankcase depth: 79.28 - 25.10 = 54.18 mm
Gasket, endfloat, offset as above: 0.35, 0.15, 64.00 mm.
RH crankcase depth: 90.24 - 25.10 = 65.14 mm
Output shaft length: 117.26 (with spacer, which stays, but not with shim, which doesn't. The spacer is thick enough that the verniers will clear the large diameter gear wheel).
Total shim thickness: 54.18 + 0.35 + 65.14 - 117.26 - 0.25 = 2.16 mm.
RH shim thickness: 65.14 - 64.00 - 0.075 = 1.065 mm.
LH shim: 2.16 - 1.065 = 1.095 mm.
Another forwarding service is ShipItTo.com . You have a US address which is great for those Ebay sellers who don't ship outside the "lower 48". They send photos of the parts as they received them. Pretty reasonable pricing. https://www.shipito.com/en/?countrycode=nz
it's not a bad thing till you throw a KLR into the mix.
those cheap ass bitches can do anything with ductape.
(PostalDave on ADVrider)
Thanks Pete i look at that sounds good mate i run out money spent 2 k on the old vfr crazy i know
I think ultimate whould be if you chould have few diffrent panels arrive and put in the one box. ;-) my 4 sides right left front
left right midde where 100 ukp each and about that to post each on one by one as had buy them as i chould afford.
Shit you can lol i sound like that add i better get one hair cut before all falls out with stress.
wow had a look cool stuff mate
Shims on order, it'll probably be a few weeks. While I was at it, I took the liberty of ordering a number of swingarm shims as well. It turns out that alignment of front and rear sprockets is very important for chain wear life and the only real way to adjust that alignment is via the shims on the swingarm bearings.
Welder back down into the garage, doing the last set of 45 degree, 25mm, 2.4mm wall thickness tube samples before attempting the frame. Welder settings were:
1.6mm tungsten, 2% thoriated
1 amp / thou thickness, equating to 94 amps
DCEN (direct current, electrode negative)
10 l/min shielding gas (argon)
filler rod specified for mild steel (forget the type but it's standard)
This went far better than earlier attempts. I had to cannibalise earlier test pieces for raw material, so took the opportunity to check their welds. One of these is pictured, hacksawed just above the weld - this was my first attempt at the neck, and I hadn't extended the tungsten or used a narrow cup. There's a massive buildup of filler but a void behind it.
The 45's shown here are all today's effort.
Getting a bit more confident - decided to go ahead on the first of the frame repairs, fusion welding the cracks at the root of the gusset.
First step was to wash the entire frame down with degreaser and rinse with water. This was done with catch trays on the folding table. Next, take the paint off at all weld areas. Every trace of paint had to go.
I started with a paint stripper disk and an angle grinder. I wouldn't recommend this - it's very easy to bump into things with the disk by accident. After a while I switched to wet'n'dry, with meths as working fluid, then just wet'n'dry on its own. A roll of cloth-backed abrasive (can't remember what the stuff's called right now) would have been very good: put a strip around the frame, push-pull, take half a diameter straight down to bare metal. Anyway, got there, with some elbow grease.
The paper can't get into the corners of MIG beads though. Acetone, applied via a rag (to soften / dissolve the paint) and a wire brush did. Final cleanup with more acetone and it was ready to weld.
Much better. Maybe a touch hot looking at that undercut, but you're on the way.
Ah, and those wee pinholes are at the end of a run? Set up your current down ramp to 4-5 sec and gas post-flow to about 10 sec and leave the dying arc on the work until it stops.
Go soothingly on the grease mud, as there lurks the skid demon
The first frame weld actually went OK. This was a simple re-melt of a weld bead, right hand top frame rail, first vertical upright. I'd seen what looked like a couple of fine cracks and wanted to be sure.
The second - repairing the very obvious crack at the root of the reinforcing gusset - didn't go well at all. Getting into a frame turned out to be quite a step up from welding dinky little sample pieces on a table. Lots of foulups, lots of distractions... at this point I should have taken a break but I had the blood up. After about five goes at it on the folding table, I finally realised that I couldn't see a thing through the mask, and this was because I had the garage door open. Sunlight was causing problems with the mask.
In the meantime I'd managed to blow a hole through the frame... shit, shit, shit. I filled it with rod toot sweet, then engaged brain (finally) and realised what the problem was. Guess what, just because one visible piece of tubing is 2.4mm wall thickness, it doesn't mean the whole thing is.
Crystal clear in hindsight. Presumably welders with more skill simply make test puddles and set amperage by that.
Afterthoughts: the X-ray technique I'd played with earlier could have told me this. If I put some samples of commercial tube next to the frame, then took a shot and compared signal count through frame vs sample, I could have a non-destructive measurement of wall thickness that way. Another way - find a wrecked frame and hacksaw the thing, then get the calipers out.
Anyway... it looks like the tubing is 1.6mm wall thickness, or thereabouts. I finally lost patience with abortive attempts to weld on the table and rejigged the frame as shown, with the weld zone flat on the workbench and relatively accessible.
Weld's pictured. It's not the best really but anything more I do to it is just going to make it worse.
Ta. Yeah, the undercut on the flank has happened a couple of times - I'm starting to think that I should file the notched tube back until it's a proportion of original thickness, say 50%? At the very edge it's paper thin. The other thing is that maybe in the neck I should turn current up a bit, since in direction of weld, the material's a lot thicker.
I've already got current down ramp and post flow, but will have to check times - probably shorter than you recommend. I know I've got to learn patience and keep the torch in place, welding rod too, during the post weld phase.
The undercut is partly torch angle and partly not enough filler. Filler rod is a heat sink, the process is basically make a puddle forward from the last deposit and centered on the joint, then dab the rod to fill the puddle and move forward again. If the torch angle isn't centered you tend to end up pulling parent material from the hot side into the puddle. You need to keep the rod just out of the arc, too where it takes just a prod to add filler, too far away and it gets out of the gas shield and all crusty. The main trick is to develop that cycle rhythm so you end up with even deposits looking like stacked coins or fish scales.
It's frustrating, you look at tredley bike frames and the welds are perfect, but they're done by either a guy that's done that particular joint a thousand times or a robot. And to be honest most motorcycle frame welds aren't flash. Yours frame was mig welded too, originally, which is a production process and never looks as good.
Go soothingly on the grease mud, as there lurks the skid demon
[QUOTE=OddDuck;1130994658]The first frame weld actually went OK. This was a simple re-melt of a weld bead, right hand top frame rail, first vertical upright. I'd seen what looked like a couple of fine cracks and wanted to be sure.
I think your doing great i chould not do this . just feel you chould make alot better if you had frame held firm and not so far into a bench
means your already having to be bent over thinking about you body posture and having relaxed arms .just a thought to try help you.
Weld looks okay its the strength your looking for i mean it looking a certain way i guessing shows flow .
am sure your inspiring many people to give things a go . dont beat yourself up frame welding must be one most demanding skills
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