Merlin DOHC Progress (2018)

One of the reasons for the delayed progress is that due to the impending redundancy i am trying to get the things done that need to be done before i 'retire'
Building my own hydraulic table to work on bikes is one of them

Full test of the table, loaded with weights (and me, i weight 81 Kgs)

Max height

Mitzi on the table.
She weighs 223 Kgs and to get the table off the deck takes 81 Bar pressure. The electric hydraulic pump i,m using is rated up to 100 Bar which takes the table capacity to just over 280 Kgs. Using the hand pump i can get that figure higher, but i don't need that capacity anyway!
Its not finished yet, still a bit of reinforcement to weld in underneath and the front wheel clamp to make. But i'm very happy with how its turned out as I have not found any other bike table that can do what this one does:- Self powered by a battery, manual hydraulic pump as well, 42" max lift height, 7" lowest height, automatic lock and auto resetting. It being a scissor lift with no floor frame means that it can be lowered down onto a floor dolly to allow easy moving.
I based it on the Handy 1200 bike lift but used a hydraulic pump and ram i already had and it just went from there...
At max height I'm eye level with the starter motor!
 
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I reckon just take a right hand cylinder head off of a Honda st1100 and bolt it on a 750 commando barrel
Use a dummy extended camshaft with a pulley on the drive side of the engine
Just drill some extra holes in the barrel to hold the head ,it already has 73mm combustion chambers
Then weld fins on the head or fit a small rad and water pump and bobs your uncle
Allen Milliyard would have that done in a morning!!
No takers then?
Oh well I guess everyone is busy!!
 

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I have a load of pics of the Merlin engine to upload. Can someone tell me how I do that? Thank you.
 
Hi Bsamat, there are two options. (1) become a VIP member @ $39 per annum then you can just drag and drop them. (2) Upload them to a sharing site, then publish the link in this thread. Personally I prefer Google drive, as they are zoomable like Peter's (dobba99) pictures above. Once you have uploaded a picture to Drive, you simply right click on it and "get link", then paste it here.

Cheers,

cliffa.
 
No takers then?
Oh well I guess everyone is busy!!
Converting a watercooled head to air cooled is an issue, CX500 4V heads are just the right size bore for B40/B44 but the water to air cooling kills it off. I have one but it sits on a shelf awaiting inspiration.
 
Thanks Cliffa, I'll give it a try. The first pic is the bike the engine was fitted in, now sporting a turbo charger (and accompanied by a box of broken cranks and twisted con rods. Draw your own conclusions!) Apparently the bike ran really well with the Merlin in it;



The following links are to pics of the engine in no particular order. The crank nut is not original, its one we had made to help turn the engine over. Have the links worked?





 
Wonderful BsaMat
Told you this was the place to look. Hope you get it running & back in the bike. Interested to hear what it sounds like.
 
Thanks Cliffa, I'll give it a try. The first pic is the bike the engine was fitted in, now sporting a turbo charger (and accompanied by a box of broken cranks and twisted con rods. Draw your own conclusions!) Apparently the bike ran really well with the Merlin in it;



The following links are to pics of the engine in no particular order. The crank nut is not original, its one we had made to help turn the engine over. Have the links worked?






Yep, the links are working well thanks !!
 
More Merlin pics. Looking down at top of head;

Exhaust port close up;

Between cam boxes;

Points! An amazing engine and old school points;

Inlet port close-up;

Crank end. Space for an alternator, apparently the bike was run with total loss electrics;


Cheers
Mat
 
PS above I meant to say NO space for an alternator in the caption for the last picture.
 
PS above I meant to say NO space for an alternator in the caption for the last picture.
Are you sure about there not being room for the alternator? I assume the bottom drive pulley is slightly too large and encroaches on the stator?
 
To be honest I'm not sure about anything with this engine. Its not so much the space in the casing that's the issue, more that the crank end is very short so I don 't think there's room for anything other than the engine sprocket, but I could well be talking rubbish. I'll post more pics as we find bits in the boxes; looks like the primary drive is all there
 
To be honest I'm not sure about anything with this engine. Its not so much the space in the casing that's the issue, more that the crank end is very short so I don 't think there's room for anything other than the engine sprocket, but I could well be talking rubbish. I'll post more pics as we find bits in the boxes; looks like the primary drive is all there
Oh I get what you mean, hard to exactly in this photo but I guess the alternator spigot has been cut off?
 
I think it is possible to turn up a female - male threaded shaft and convert a none alternator crank to take an alternator.
 
Alan and John (who were Merlin engineering) made this engine for sidecar cross so it is understandable that it has a short crank i.e. no provision for an alternator.
One thing that does puzzle me, This engine plainly has a modified set of Mk3 crank cases. The Motorcycle Weekly article (from 1980) that i posted on this forum a few years ago states that Mk3 cases must be used 'as they are thicker'
When i was picking John and Alans brains about it when i bought the drawings (for the D.O.H.C.) They insisted that was not the case (excuse the pun) John said that the Mk3 crankcase was thinner and said to use the earlier case with a reinforcement ring shrunk and welded on.
Not wanting to take Mitzi apart just to measure her crankcase thickness and not having an earlier crankcase anyway can anyone confirm the thick earlier / thin Mk3 case question?
 
I cant see them being thinner but stronger.
I have an empty set here that I could weigh and measure but it won't mean much without a comparable.
A friend does have an earlier 850 set, one day we'll compare.
 
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