Engine cradle

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I have the engine cradle out for paint , 1974 850 cc .
Should I weld 2 nuts on the swing arm tube to support the swing arm axle with 2 bolts ?
Is this recomended ?
What possition should they be at ?

The front engine Mount bracket has 3 holes . 2 for the crankcase , what is the last hole for ?
I see that 3. hole is also seen at the Mrk. 3 bracket .

Michael from Denmark , total basketcase reassemble . 1974 Mrk. 2A 850 cc
 
Egholt said:
The front engine Mount bracket has 3 holes . 2 for the crankcase , what is the last hole for ?


Later front Iso. brackets often have that extra hole, but it doesn't appear to serve any particular purpose, as far as I know.
 
Egholt said:
I have the engine cradle out for paint , 1974 850 cc .
Should I weld 2 nuts on the swing arm tube to support the swing arm axle with 2 bolts ?
Is this recomended ?
What possition should they be at ?

The front engine Mount bracket has 3 holes . 2 for the crankcase , what is the last hole for ?
I see that 3. hole is also seen at the Mrk. 3 bracket .

Michael from Denmark , total basketcase reassemble . 1974 Mrk. 2A 850 cc

The swing arm tube is thin, the nuts will locally pucker the tube when bolts are tightened. The split shaft collar type mod is a better (stronger) solution, IMO.
 
You'll notice on the pivot shaft of a new shaft it has the flat spots so it can be used on the MK111 with cotter pins.
Those flat spots are not 90 degs to the center screw hole in the top of the shaft.
With the cradle out it is easier to align the flat spots so you can mark the tube for drilling.
The use of the split collars is the way to go.
I did mine while still in the bike and it didn't come out perfect but still works.
Notice the lube hose. I copied it from someone on this site.


Engine cradle
 
Thanks for all your info .

I will go for the The split shaft collar type .

Will the best set-up be if I have the collar set so far from each other as possible ?
Then grind flat spots on the spindle 90 degree from the top bolt . (no threaded holes)
Or will it be better if I can thread 2 holes ?

Like the oil tube solution .

I will get a distance piece and a long bolt for the 3. hole in the front Isolastic bracket , to reinforce the bracket .

Michael
 
Egholt said:
I will get a distance piece and a long bolt for the 3. hole in the front Isolastic bracket , to reinforce the bracket .

I don't believe the bracket needs any additional reinforcement? Attempting to add a brace that close to the welded tube to me at least, would seem to be a complete waste of time and only adds a little unnecessary weight.

Engine cradle


Also, whilst you will probably find that a rod or bolt will pass through the holes with the bracket in situ, any substantial distance piece is likely to clash with crankcase joint.

Engine cradle
 
The other way is to mod your rear engine mount to take the cotter pins like the mk3. Here's some pics of my 1968 that I've done.
 

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Guido said:
Notice the lube hose. I copied it from someone on this site.

Good idea on the lube hose. Do you have to loosen the end caps to allow air escape so the gear lube can flow? On my '72 I unscrew the zirk and pump gear lube into the hole using a basketball inflation needle connected to the pump hose. It works, but not very well. Takes a long time to get much in there.
 
Egholt said:
I have the engine cradle out for paint , 1974 850 cc .
Should I weld 2 nuts on the swing arm tube to support the swing arm axle with 2 bolts ?
Is this recomended ?
What possition should they be at ?

The front engine Mount bracket has 3 holes . 2 for the crankcase , what is the last hole for ?
I see that 3. hole is also seen at the Mrk. 3 bracket .

Michael from Denmark , total basketcase reassemble . 1974 Mrk. 2A 850 cc

That 3rd hole is a HOBOT hole.
 
illf8ed said:
Guido said:
Notice the lube hose. I copied it from someone on this site.

Good idea on the lube hose. Do you have to loosen the end caps to allow air escape so the gear lube can flow? On my '72 I unscrew the zirk and pump gear lube into the hole using a basketball inflation needle connected to the pump hose. It works, but not very well. Takes a long time to get much in there.


you don't have to worry about that because the "o rings" don't do that good a job. It was mentioned once on this site why they don't work so well. It was because most of us haven't got the skills to compress them and get them in the in the right position without slicing them if you reduce the clearances to 1-4 thou.. It is something I neglected to take note of when I did my 750 about 36 years ago. I guess I was still a novice mechanic back then.. the 850 is the same. At least I know the oil is getting through when the level goes down every 3 months or so. Makes a slight mess under the bike when parked but that's what newspaper is for isn't it.

I also notice you guys that are grinding flats and or using the split collars, that you haven't thought about the law of leverages. I would suggest anyone else that does that should put the fittings as hard up to the inside of the cradle as possible.
I am still at a loss as to which microscopic amount of play is causing the flexibility of my rear swing arm. My iso's are tight and I have used hard nylon type rubbing washers in them.
I priced out those collars in NZ and was told about $45.00 each. I decided to make my own at some stage. [ when I get a ROUND TUIT ]
Dereck
 
Thanks for that clarification, I read "additional brace" and " reinforcement" and started thinking WELDED in stuff... oops! :oops:
 
Yes indeed the extra holes in front mount are where I got inspiration for useless holes. I'd add more holes but Peel case its in alloy and Trixie stays factory no brainer. Bracing front mount is as sensible as me bracing the space inside tires. Also if linking to rear of cradle good to tie rear plates together. What needs a cross brace are the front down tubes mainly to stiffen them from torsion on each tube axis and in plane of both tubes. I capped Peel's spindle reservoir tube with air porous filter though would drain out fast enough any way. Serious surgery LAB to fit the robust lock bolts. The lesser motivated should definitely go with collars and take extra care to get them rust proof from road blast if not covering protecting by oily leakage road grime.
 
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