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CB750F2 .... silk purse from a sows ear.
SumpMagnet:
Today we got something useful done. Aside from cleaning and trying to get paint and rust off..... we sorted the broken No2 carb.
The problem was the bracket that holds the throttle cable. The bracket locates to No2 carb with a screw and a peg cast in the carb body. The peg had sheared, using a little cast nub on the carb as a stop...and that had cracked the top of the carb body.
The mission....re-instate the peg and patch the body to keep things airtight.
The flat square area just above and right of centre is where the peg used to be. I checked the depth of metal, and drilled a 1.5mm pilot hole as near centre as I could. I checked the depth and made sure I did not drill too far in so as to break through into the carb body and cause more issues than I solved! The bit I had that split was above the machined part the carb slides move on...but this is not. So blind hole it must be!
After the 1.5...we went again with a 2.5mm and tapped it with a 3mm thread. Fortunately...I have all this stuff in small size for my other hobby...Rc cars...and I also had a good seelction of cap-head M3 bolts. The heads on these were a close match to the original peg. The plan being to screw one in to form a new peg.
The bolt head was a bit too big...but shoving it in the drill and running it over a fine file soon had the thing down to teh size I wanted. A quick dip in solme silver paint made sure it was rust proof again! I hate tapping threads with small taps and blind holes....you have to be SO careful not to bottom the thread as it will strip it or break the tap. Neither would make me happy.....
The bolt was trimmed to size with the Dremel, using the old 'put a nut on first so taking the nut off cleans the thread' trick. Screwed the bolt in with a dab of threadlock to make sure it stayed where I put it. It all went together like a little sweetly :)
The final step was to stop-drill the crack to relieve pressure and to channel the crack a little with the Dremel to make a nive valley for the epoxy to sit in. Tried to build a little fillet of epoxy on the outside to support the crack, but not so much it wasn't neat anymore. A little brush over with aluminium coloured paint on the outside should help to hide the repair if the epoxy yellows.
The bracket sits nicely and the peg should be stronger than the previous casting ever was.
The only slight issue with the job was the half hour I spent looking for the screw that holds the bracket in. I checked in carb bag 3 ..... and there was no trace. Checked the bench, the shelf...everywhere.
The mystery would have been solved quicker if I had remembered the bracket was on carb 2 ...... no harm done.
SumpMagnet:
Not had much time to work on the bike over the last couple of weeks, but small progress has been made. Work has been interfering but the worthless bunch of petty ingrates who employ me have allowed me the grace to spend some time otherwise engaged while they work out whose lifeless corpse they could best employ to climb higher up the greasy pole.....
That aside....
I thought I would have a go at breaking down the forks so I could get them sent off for rechroming while I figure out how one goes about measuring crankshafr bearing clearances.....
wish I had chosen something else...but oh well.
I have had many a fine tussle trying to undo the damper bolts at the bottom of the forks, and expected the same again here. Nope. Both undid really sweetly with just the pressure opf the spring stopping the damper from turning. This was clearly just the old beast trying to lull me into a false sense of security....
Next I went to undo the fork caps and get the springs out. Had to bolt the tubes back into the yokes to grip them, but hte first one undid. The second one did not buidge. Will not budge and broke free from the vice damaging the steering stem bearing cover that was still on it. The top nut has started to chew and still the damn thing won't budge. Breaker bar and the thing will twist in the yokes before it undoes. Tried shocking it and no joy. Next...I suppose I will have to try heat. I suppose the o-ring in there will want replacing anyway...
Anyway...Out with the damper bolt so I could get the tube out and remove the old seal. A lot of rust under the dust cap when I finally got that off. It was cracked and rock hard. I soaked it in ht water and pulled it out with moile grips like a rotten tooth. Then I pop out hte retaining clip...or I thought I had. What I had was half a clip. The other half remains in the groove. Corroded firmly in place. It's currently soaking in penetrating fluid before I try and pick it out. Had broken clips before...had rusty clips before. Never had one corroded in place or actually rusted clean through. The alloy, however, was not corroded at all. No fur...just red rust.
When that finally shifts I can have a go at getting the damn fork seal out. I expect another battle...........
Bryanj:
Fork top nut impact hammer with 6 sided socket, seal make sure you do not damage the surface oinside the slider, seen lots of leaks from that. Broken circlip may respond to heat from one of the canister plumbers torches---i use those on the master cylinders to clear out all the crap and make the clip moveable.
SumpMagnet:
I hear you on the seal ....made that mistake before. Will be popping it in hot water and try to pull the seal....no metal tools trying to pry it out. Will try heat on the clip too....but can't start on the seal until the clip is sorted. I really don't want to damage the groove either.
My impact screwdriver has a socket 1/2" drive thing on it. Will try that.
Bryanj:
I was think more of a widy hammer like tyre fitters use on wheels, maybe you can take it to your nearest tyre shop and ask a favour? As to the clip and seal the small torch will not damage the groove just loosen all the crap on the metal and the seal is shot anyway.
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