1950's 4 cylinder Norton - Page 6
Close

1950's 4 cylinder Norton

This is a discussion on 1950's 4 cylinder Norton within the News forums, part of the Caferacer.net Forums category; [QUOTE=Cyorg;471626]That is of interest. I have been wondering about that lately. I have a crank W/O sludge trap and have been waffling back and forth ...

Page 6 of 6 FirstFirst ... 456
Results 51 to 59 of 59
Like Tree9Likes

Thread: 1950's 4 cylinder Norton

  1. #51
    Senior Member jalsteve's Avatar
    Join Date
    Aug 2014
    Location
    Herts, UK
    Posts
    532
    [QUOTE=Cyorg;471626]That is of interest. I have been wondering about that lately. I have a crank W/O sludge trap and have been waffling back and forth abound running solvent through it for a while. The crank is nice and straight and the big end is still as it should be, so I don't want to monkey with it. My only fear is dislodging some of the crap (assuming there is crap) from the oil passage and it not finding its way though the big end bearing. I probably worry too much and the new detergent oils might move it along eventually anyway. Better to have a go at it now rather that have it go through the bearings while running under load.

    I was thinking of asking you what sort of piston clearance you run in the Manx engines. The factory notes mention anywhere from .008 to .019 (500 alloy barrel) and on Ian Bennett's site, he says don't run any tighter even with modern pistons or they will seize. I would think that you could run a little tighter with modern pistons and the rings would be happier Y/N?[/QUOTE

    If diesel doesn't dissolve the crap then detergent oil is unlikely to touch it. Good thing is most multi cylinder cranks have galleries you can drill out if you are worried, then clean and reinstate the plugs. On Norton twin cranks I drill the web and install a plug which I can remove later if I need to which give access to the trap. If the crank is plain bearing you could put it in the ultrasonic?

    Piston clearance is a funny one. Original pistons fitted by Norton (Wellworthy) are heavy thick cast and likely to kill your cat if one falls from your work bench. They can take some warming up too and they can grow a lot therefore despite being forgings. More modern pistons from Omega or similar are a fraction of the weight are stable and grow less. Basic rules apply when all is new; follow the rules of the piston manufacturer! Problems occur when the cylinder has done a little work, probably s/hand and the only piston you have is a modern light weight as it might not grow into the hole in the cylinder! You also need to consider oil too as castor oil forms a varnish on engine surfaces and along with splash lubricates and even in the event of starvation this varnish still lubricates. Modern oils and synthetics have high film strength and don't build a varnish film - simply put you can run a larger clearance with castor. Don't be tempted to run thick mono grade synthetics like Amsoil 60 or 50 race unless the piston is modern and the cylinder is bored to match. To be sure of the bore size use a bore gauge and measure top to bottom. I have in the past re sleeved an original bore to match a new lightweight piston which is a bloody shame when pistons graded in in .003thou sizes would be great. Back in the day you could get graded pistons!

    If your cylinder is new from Bennetts hopefully they will have supplied it needing a final hone to suit the piston to be used? And use R.

    I find on engines that will be used in real anger a larger clearance works best.
    Lite the blue touch paper and stand well back!

  2. #52
    Senior Member Cyorg's Avatar
    Join Date
    May 2014
    Location
    B.C.
    Posts
    980
    It's a Norton single crank. I'm going to try the parts washer (solvent tank). I'm in the process of rigging up a marine remote oil filter to the parts washer pump just to make sure what goes through the crank doesn't have any crap in it. (even though the solvent is pretty much new) The existing filter only removes the large lumps and the proper filter should cut the flow down from the new pump to a more manageable level.

    The barrel from Bennett comes with a 78mm bore, so it'll require boring, plus the spigot is 1/4", so I need to cut it down to 1/8. I should have got him to cut it before he shipped it. The part that confused me about the clearance is his pistons are made by Omega. They are in his home town and he got them specially made, so perhaps they have characteristics similar to the originals. I do have this, but I don't know who the maker is and I don't know the CR. It looks like a lot to me and I don't really want to fart around with alcohol. Nor do I want to over stress anything below the barrel. It won't be ridden in anger for fear of doing irreparable damage to my wallet. It's going to be a bit of a mongrel, so won't be that fast anyway. I'll be happy if I can just get it to make all the proper noises and smell nice. Anyway... the piston.. It's new and is stamped std. The brown goo is the dreaded cosmoline. There isn't a whole lot of meat on the crown, so can't remove much.... not that I want to go that route.

    Name:  Piston.jpg
Views: 45
Size:  60.6 KBName:  Piston2.jpg
Views: 43
Size:  62.4 KBName:  Piston3.jpg
Views: 42
Size:  68.6 KB
    Last edited by Cyorg; 01-02-2017 at 08:09 PM.
    "Non urinat in ventum"

  3. #53
    Senior Member jalsteve's Avatar
    Join Date
    Aug 2014
    Location
    Herts, UK
    Posts
    532
    Quote Originally Posted by Cyorg View Post
    It's a Norton single crank. I'm going to try the parts washer (solvent tank). I'm in the process of rigging up a marine remote oil filter to the parts washer pump just to make sure what goes through the crank doesn't have any crap in it. (even though the solvent is pretty much new) The existing filter only removes the large lumps and the proper filter should cut the flow down from the new pump to a more manageable level.

    The barrel from Bennett comes with a 78mm bore, so it'll require boring, plus the spigot is 1/4", so I need to cut it down to 1/8. I should have got him to cut it before he shipped it. The part that confused me about the clearance is his pistons are made by Omega. They are in his home town and he got them specially made, so perhaps they have characteristics similar to the originals. I do have this, but I don't know who the maker is and I don't know the CR. It looks like a lot to me and I don't really want to fart around with alcohol. Nor do I want to over stress anything below the barrel. It won't be ridden in anger for fear of doing irreparable damage to my wallet. It's going to be a bit of a mongrel, so won't be that fast anyway. I'll be happy if I can just get it to make all the proper noises and smell nice. Anyway... the piston.. It's new and is stamped std. The brown goo is the dreaded cosmoline. There isn't a whole lot of meat on the crown, so can't remove much.... not that I want to go that route.

    Name:  Piston.jpg
Views: 45
Size:  60.6 KBName:  Piston2.jpg
Views: 43
Size:  62.4 KBName:  Piston3.jpg
Views: 42
Size:  68.6 KB
    Parts washer for the crank= perfect. I would also pump through also. If the crank has any rough cast faces concentrate effort there as that's were the crap sticks and hides. I never put assembled roller bearing cranks or assembled anything with working surfaces in contact in an ultrasonic tank.

    Why on earth would a supplier send anything unfinished! The piston is massive but they were! If both piston and cylinder came from the same place why on earth did he not finish or offer too finish the cylinder to piston clearance? And if he knows the engine year why did he not finish the spigot? Seems you have money still to spend in these parts. I would ask Bennetts for a piston clearance figure top and bottom of the cylinder (if different) and not a range. Just tell them the shop who will be honing the bore need to know. Also you need to be careful with compression ratios on these old engines they need good high compression figures to run well. The won't run at all well if its too low and will be a bitch to start. You are going to need to build the engine and measure all, there is no other way out of doing this; The Manx engine is an engineering fitters dream, valve drops at TDC, exhaust valve to piston clearance and valve to valve overlap. Get your box of baseplates and shims ready you are going to need them, cam timing is simple enough.

    For info I am not an early Manx expert but have worked on a few (also R7 and k10, Excelsior Manxman) and they are simple enough but its all in the running clearances. Good luck.
    Lite the blue touch paper and stand well back!

  4. Remove Advertisements
    CafeRacer.net
    Advertisements
     

  5. #54
    Senior Member Cyorg's Avatar
    Join Date
    May 2014
    Location
    B.C.
    Posts
    980
    Yes plan on making a fitting for the timing side of the crank, so solvent can be pumped through the big end for a day. The ultrasonic cleaner hasn't arrived yet and it's not big enough to hold a crank assembly anyway, so I won't be tempted. Good point about the working surfaces... didn't think of that. I've been cleaning transmission bits getting them ready for the ultrasonic. There has to be an easier, less time consuming, more environmentally sound way to pre-clean parts. If I had the time and energy, I'd try building a wash cabinet with a good filtering system and a high pressure water pump that I have laying in the "some day I might use it pile".

    I just got the cylinder from Bennett, it was a trade for another cylinder (for a later engine) that needed work also. If I had my wits about me, he would have cut the spigot if I asked. The piston I've had for a while, but don't know much about it's history.
    I haven't done any Manx stuff, but have some limited experience with Inters. I do have a box with baseplates and shims (there is lots of play dough in the house), plus some shim stock if I have to go that route I'm still a ways away from assembling this thing, but want to clean inspect and sort things so I know what to track down. I do have a couple new double row ball bearings for the bevel drives, so I'm thankful for that. I can also order stuff randomly as the budget allows. I'll need time to recover from the mag rebuild which should be completed in a few weeks.
    "Non urinat in ventum"

  6. #55
    Senior Member jalsteve's Avatar
    Join Date
    Aug 2014
    Location
    Herts, UK
    Posts
    532
    Quote Originally Posted by Cyorg View Post
    Yes plan on making a fitting for the timing side of the crank, so solvent can be pumped through the big end for a day. The ultrasonic cleaner hasn't arrived yet and it's not big enough to hold a crank assembly anyway, so I won't be tempted. Good point about the working surfaces... didn't think of that. I've been cleaning transmission bits getting them ready for the ultrasonic. There has to be an easier, less time consuming, more environmentally sound way to pre-clean parts. If I had the time and energy, I'd try building a wash cabinet with a good filtering system and a high pressure water pump that I have laying in the "some day I might use it pile".

    I just got the cylinder from Bennett, it was a trade for another cylinder (for a later engine) that needed work also. If I had my wits about me, he would have cut the spigot if I asked. The piston I've had for a while, but don't know much about it's history.
    I haven't done any Manx stuff, but have some limited experience with Inters. I do have a box with baseplates and shims (there is lots of play dough in the house), plus some shim stock if I have to go that route I'm still a ways away from assembling this thing, but want to clean inspect and sort things so I know what to track down. I do have a couple new double row ball bearings for the bevel drives, so I'm thankful for that. I can also order stuff randomly as the budget allows. I'll need time to recover from the mag rebuild which should be completed in a few weeks.
    Thought Bennett supplied the piston. Measure the piston and send to Bennetts and ask for running clearance. They may want to know who made the piston though - I would buy another of known origin if I could not ID the maker of a piston I have its too risky*. You might be able to turn the excess spigot off but holding the bore is difficult as its a big lump. I would expect the engineering shop that will final cut the cylinder to size can shorten the spigot.

    * I have perhaps a dozen piston for period single cylinder race bikes that I cannot ID the maker, none are marked, one I know came from Al Gunter. All sit neglected on a shelf.
    Lite the blue touch paper and stand well back!

  7. #56
    Senior Member Cyorg's Avatar
    Join Date
    May 2014
    Location
    B.C.
    Posts
    980
    Crank bath is ready. Hope the Fram filter does it's job.

    Name:  Norton crank bath.jpg
Views: 27
Size:  100.1 KB
    pwalo likes this.
    "Non urinat in ventum"

  8. #57
    Senior Member CaTacL1sm's Avatar
    Join Date
    Feb 2009
    Location
    Fort Knox, Kentucky
    Posts
    1,271
    what's the purpose of this?

    and how does it work
    I thought that a cafe racer was a custom that you could do whatever you wanted and there is no right or wrong.

  9. #58
    Senior Member Cyorg's Avatar
    Join Date
    May 2014
    Location
    B.C.
    Posts
    980
    Quote Originally Posted by CaTacL1sm View Post
    what's the purpose of this?

    and how does it work
    It's an old crank and the engine doesn't run a filter, just a screen to keep the lumps out. There is no sludge trap in the crank that you can remove and clean out. It's not like a newer cross drilled crank that use can just clean with gun barrel cleaning rods etc. This would have to be disassembled to clean that way and you generally want to avoid taking these cranks apart unless you have to. It's hard on them and finding competent people (in my neighbourhood) to machine, reassemble and true them is difficult. Pumping solvent or diesel as jalsteve suggested, through the cranks oil passage will hopefully remove any crap that may have collected along the oil passageway and big end bearing. This crank has been sitting for a long time in an environment that wasn't all that great. It may have something living in it that needs to be evicted.
    CaTacL1sm likes this.
    "Non urinat in ventum"

  10. #59
    Senior Member CaTacL1sm's Avatar
    Join Date
    Feb 2009
    Location
    Fort Knox, Kentucky
    Posts
    1,271
    Neat, thanks for the explanation
    I thought that a cafe racer was a custom that you could do whatever you wanted and there is no right or wrong.

Page 6 of 6 FirstFirst ... 456

Sponsored Links

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Similar Threads

  1. 1950 BSA B33 Help
    By 4Nines in forum Technical
    Replies: 23
    Last Post: 05-25-2016, 09:43 PM
  2. Replies: 0
    Last Post: 05-23-2015, 10:05 PM
  3. 1963 Norton Electra 1962 Norton Navigator $300
    By nic579 in forum Bikes For Sale
    Replies: 13
    Last Post: 10-08-2011, 10:36 AM
  4. 1950 500 CC Comet on ebay
    By Eurago in forum Bikes For Sale
    Replies: 1
    Last Post: 02-20-2009, 12:06 PM
  5. 1950 footage
    By Pete Casper in forum Vintage Motorcycle Racing
    Replies: 0
    Last Post: 12-24-2007, 09:23 AM

Search tags for this page

molnar norton 500 four

,

molnar norton 500 four cylinder

,

molnar norton inline four engine

,

norton 4 cilinders

,

norton 4 cylinder

,

norton 4 cylinder motorcycle

,

norton 4 cylinder racing motorcycle,andy molnar

Click on a term to search for related topics.