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Rev3 Top End Inspection


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That stuff's a reaction between different coolants is it? makes sense, I couldn't figure out how it got there I wondered if it was rad weld or something. It seems to have coated the parts of the cooling system and there were clumps of it within rubber hoses and actually there were some lumps in cylinder.

I've submerged the water pump cover in petrol and fairy liquid so far to try and dissolve it to no avail but I dropped a flek of it in some watered down spirt of salts and that dissolves it pretty quick but it says on the tin not to use it on aluminium so I need to find something Ali friendly that I can rely on to clean waterways in rad with out visual inspection.

Would you or anyone else have any suggestions how to shift it?

As for replacing main bearings and seals I can't detect any play through fly wheel and there isn't any oil leaking through seal behind fly wheel by the look of it but when I took sump guard of the bottom of bike i noticed a lot of oil over the bottom of the engine and the rubber matt the engine sits on which made me wonder if the crank case seals were leaking oil, I just got the vibe it wasn't from where the oil has been drained off previous.

Also the coating on engine cases had bubbled where the cases meet which I scraped off previous to pictures which suggests to me the same and finally it looks like someone's got got the flat head out to prize the casings apart which is really making me wonder?

The engine isn't off the bike yet but I'm only 3 fixings away, all comments welcome.


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See if your radiator tubes are clogged.

I do not know anything that shifts this crud for certain.

Try radflush. Run the bike with a piece of calgon (dish washer cleaner) in the system and just use water - no antifreeze. Change this regularly

Try Clarkes aluminium cleaner (machine mart). Just a guess but maybe mix it 1 part cleaner to 4 parts water. If you do this don't use antifreeze and flush the system thoroughly as soon as the bike cools.

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I had some ds40 central heating cleaner lying around which is suitable for cleaning boilers with aly heat exchangers so I submerged rad and water pump cover in a solution of that today which has dissolved the gunk totally.

The cylinders off at the re platers and I'm hoping the water ways will come back clean so I won't need to touch that.

The hoses were lined with this crap but where in the past some ones got a bit heavy handed tightening the jubilee clips that part of the hose's are crushed and there's some cracking of the rubber so I am going to get a set of replacements to put on.

Going back to checking the squish clearance is the technique to torque the head down with gasket in place and torque cylinder down with out a gasket kick engine over and take measurement of solder add on thickness of base gasket and that would tell you what thickness of gasket(s) to use, other wise if you install gaskets and torque down to find out your squish isn't to spec you are another

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I check the squish without any gaskets and very little torque, head and barrel just nipped down. I use resin cored colder about 6mm long, one piece at inlet side, the other at exhaust side. I turn bike over slowly with spanner on flywheel nut. I then take gasket thicknesses into account when doing the squish calculation.

I often make my own base gaskets from either proper gasket paper or serial packet card. I stick it tot the barrel with blue hylomar and put copasliip on the crankcase face. I often reuse head gaskets, I just clean the old ones and then coat them with a mix of thinners and hylomar.

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Ok dadof2 sounds like a good plan I will get some hollow solder and have a larger bowl of sugar puffs in the morning!

When you mentioned about doing mains and seals to be good for 5 years you got me thinking,

I might well go for that while I'm so close for piece of mind although I can't detect any up and down play through fly wheel or con rod at 6 and 12 o'clock.

So to do that I would need a tool to hold clutch basket to undo nut? and would I need any other specific tools to split cases ect or do they pull - pry apart with the aid of the cut out to the front of the engine as one of the pictures I previously posted.

Another thing I haven't mentioned yet is when I bought the bike the jubilee clip that go's round the rubber that attaches to inlet of carb was undone and I didn't realise until I had already riden it for a few hours, a fellow rider where I was riding said the bike sounds like it has a air leak so I checked what I could see and that was undone, it turned out afterward he ment downstream of the carb unbeknown to me initially, after when I got the bike home and stripped carb down

there was a fair bit of crud in the bowl and like previous posters have mentioned there were signs on the piston-cylinder of crap entering.

Also at that time I had air box ect off and it had holes drilled in it and plenty of dirt in.

So really I got to split cases just to get any crud from the bottom end haven't I.

Thanks for your input and to the site in general its a invaluable sorce for a novice trialer and mechanic.

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Hi again

Yes you need a clutch holding tool - cheap and quick on Ebay or a number of online suppliers

Also you will need a flywheel holder and puller I think Sammy Miller does all 3 tools

Crank cases pull apart easy enough

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