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Royal Enfield Motorcycles => Vintage Royal Enfield => Topic started by: Roger ONeill on August 04, 2013, 04:50:48 pm

Title: Another question about identification
Post by: Roger ONeill on August 04, 2013, 04:50:48 pm
Good morning All,

I have just joined this forum and have done a fair amount of reading but still need a bit of help if  possible. I have read all of Graham Scarth's notes on identification and have a bit of a handle onit,but still require some clarification. A friend and I are trying to restore what we were told was a 1958 Constellation. As the work progressed we started to question if indeed it was truly what we thought. When we picked up the machine it was not assembled and when we came to stalling the connecting rods that came with it we found that the rods fowled on theinside of the crank cases so we started to do a little research and have come to an impass. The numbers on the back of the cases do match (sm1726) so we have a pairedset of cases. The true engime number on the front of the cases (SM2736 HDM) indicated that the bike is a 1956 Super Meteor according tothe lis that was published in one of Accessory Marts cataloques. The numbers on the frame and the left of the crank case (7T 4852) still poses some questions. We were hoping that someone could shed some light on the actual model and year of this machine and also provide some information about the correct connecting rods to be used inthis engine.
Thanks,
Roger
Title: Re: Another question about identification
Post by: ERC on August 04, 2013, 06:32:22 pm
If it's an original 1956 the rods run directly on the crankshaft with no bearing insert. Did yours have the insert if so this may be your problem.  ERC
Title: Re: Another question about identification
Post by: barenekd on August 04, 2013, 08:27:33 pm
It sounds like you might have rods that take the bearings and are trying to put them in the earlier model case. I think the bearing version came out in '58.
Bare
Title: Re: Another question about identification
Post by: Bullet Whisperer on August 04, 2013, 09:14:21 pm
I don't want to muddy the waters, but last year I restored a one family owned from new 1953 Meteor 700 twin. It had a 7t followed by three digit number. Among other things, the big ends were worn and there were shell bearings in the conrods of this machine. The crank was reground and new big end shells were fitted.
After working on an early '500 Twin', I was of the understanding that the integral big end type conrods could be replaced by the separate big end shell type ones. I also remember having a hell of a struggle splitting and reassembling that 500 Twin's crankcases, due to lack of clearance for the small ends of the conrods. If I remember rightly, I put the crank into the timing side main ok, but I think I put the drive side main on the crank mainshaft, dipped the small end of the conrod under the cutaway in the drive side case and then fed the whole main bearing into the drive side case, which was pre heated for this purpose.
  I have added some pictures of the conrods from both these machines, if they might help in any way.
 B.W.
Title: Re: Another question about identification
Post by: ERC on August 05, 2013, 01:04:39 am
Could be they have a later crankshaft. I'm pretty sure the late ones hit the cases when installed in an earlier crankcase. 1957 was the year they changed to shell bearings.   ERC
Title: Re: Another question about identification
Post by: Roger ONeill on August 05, 2013, 01:11:38 pm
Good Morning Agaain,

Thank you for the responses. We are  little wiser as a result of your answers to our question. B.W. thanks for the hints about installing the crank in the cases, but we are getting pretty good at that. We have had the darn thing apart for what seems like a hundred times trying different rods in the cases, but all of the ones we tried had the shells and that may be the problem. The fowling occurs when the crank is being turned.
Do you feel we are correct in assuming that the engine is from a 1956 Constellation? If that is the case does anyone know where we could source a correct pair of rods that are +10. We had to have the crank turned due to it condition. We have looked at the Hitchcock site and they are temperarily out of stock of the rods for the 1956 motor. Thank you for your help inadvance.
Cheers,
Roger
Title: Re: Another question about identification
Post by: ERC on August 05, 2013, 01:25:48 pm
Hi, It sounds like what I said above you've got an early case and a later crank that won't fit the early case. Have you tried to assemble the crank into the case without the rods on it and see if it binds? ERC
Title: Re: Another question about identification
Post by: Roger ONeill on August 05, 2013, 01:57:30 pm
Hi ERC,

The crank fits the cases beautifully, the problem arises when we bolt the rods to the crank.
Cheers,
Roger
Title: Re: Another question about identification
Post by: Bullet Whisperer on August 05, 2013, 02:08:44 pm
Do you have the conrod bolts with the tapered heads, as in my second picture? I remember reading these were introduced to solve clearance issues within the crankcases on certain models. Just a thought.
 B.W.
Title: Re: Another question about identification
Post by: ERC on August 05, 2013, 02:50:55 pm
If they rods spin easily when not in the case then Bullets suggestion most likely is the problem.  ERC
Title: Re: Another question about identification
Post by: Roger ONeill on August 05, 2013, 03:43:54 pm
Hi Gents,

We have tried both types of bolts, those with a taper and those without,but Iwill have o go backand try to remember which rods we tried which bolts with.
Cheers,
Roger
Title: Re: Another question about identification
Post by: High On Octane on August 05, 2013, 04:11:13 pm
Have you tried talking to the people at Hitchcocks?  They are familiar with all the internals on all the different motors.  Perhaps they have some insight on what you might be missing?  ???

Scottie
Title: Re: Another question about identification
Post by: classicrider on August 06, 2013, 01:13:38 am
Roger,this may help you.Look down the last page for crank info.
Colin
Title: Re: Another question about identification
Post by: ERC on August 06, 2013, 01:35:25 am
Classic, that is a great chart, the best I've seen. Right from my old hometown.  ERC
Title: Re: Another question about identification
Post by: classicrider on August 06, 2013, 10:36:57 am
Glad you like what you see ERC.
Does anyone know how many crankcases RE used for the 700cc series.From my reading of this there was only 2,the original 700 Meteor was the same case as the '56-'57 SM and trailblazer,before they increased the crankcase size so they could fit the 1.8750"journal and the insert bearing conrod at the same time.But i'm not sure.
I'd be interested to know if there in fact was 3 different crankcases
Problem for Roger here is RE didn't place a part number on there cranks.Maybe if you could measure up the journals Roger we can take it from there
colin
 
Title: Re: Another question about identification
Post by: Roger ONeill on August 06, 2013, 11:44:30 am
Good Morning again,

Thanks for all of the help. I received the chart from Hitchcock's and indeed it is very helpful. So it has been decided that we have a 1956 Super Meteor or Trailblazer. Now all we have to do is find a pair of the correct rods that are +10 to fit our ground crank. Any suggestions besides Hitchcock's as I do not think they have any in stock.

Cheers,
Roger
Title: Re: Another question about identification
Post by: Bullet Whisperer on August 06, 2013, 01:55:13 pm
This is a very long shot, Roger, but you could try Burton Bike Bits or a guy called Keith Benton, from Grange Over Sands [if he is still going in any way, shape or form]. I just Googled 'Keith Benton Royal Enfield' and some results and links came up. Both are in the U.K., by the way.
 B.W.
Title: Re: Another question about identification
Post by: Roger ONeill on August 06, 2013, 03:53:01 pm
Thanks B.W.,
I will check both of these out later today.
Cheers,
Roger
Title: Re: Another question about identification
Post by: barenekd on August 06, 2013, 07:20:12 pm
From what I recall, but this is going back many years, but I don't think there were rods made undesized for ground cranks. It seem that the procedure was to clean up the crank with as little metal loss as possible, then mill the mating ends of the rod slightly to take up the clearance. Kinda weird, but as I recall, that was the way it was done! WE're talking about 1 or 2 thou corrections, not 10 thou!
Bare
Title: Re: Another question about identification
Post by: ERC on August 06, 2013, 08:28:21 pm
They did make .010 and .020 rods to fit the non shell crankshafts. They had shims on 1953 and back Chevys to correct play on the crank is what I believe your talking about.  ERC
Title: Re: Another question about identification
Post by: barenekd on August 06, 2013, 09:08:15 pm
the old Chevies had melted babbitt poured onto the rods, then honed to size.
Could work on these, too! Not sure how it would hold up under the higher RPM, but at least they have oil pressure. The Chevies were lubricated just by splash.
Bare
Title: Re: Another question about identification
Post by: Roger ONeill on August 06, 2013, 09:10:17 pm
We were wondering if we picked up a set of rods that were used without the shells and had them re-sized to accept the +10 shells if that might work
Title: Re: Another question about identification
Post by: Roger ONeill on August 06, 2013, 09:27:19 pm
Hello All,
I have read through all of your responses again and we think we have a vague idea about the problem. WE tried to locate Keith Breton, but it looks like he was trying to sell his business back in 2003 and there was little else on the web about him. Burton Bike bits only lists the latest connecting rod so I have sent a note off to Hitchcock's again to see what they have to say about the lack of shell rod. We will let you know about the progress.

Cheers,
Roger
Title: Re: Another question about identification
Post by: barenekd on August 06, 2013, 10:35:56 pm
Quote
We were wondering if we picked up a set of rods that were used without the shells and had them re-sized to accept the +10 shells if that might work

I highly doubt that there would be enough meat on them to clear the bolt holes.
Bare
Title: Re: Another question about identification
Post by: ERC on August 06, 2013, 11:19:07 pm
Will be interesting to see what Hitchcocks has to say. Have you tried to install the crank with the rods on in each crankcase half with the other side not on and seeing where it might hit?  ERC
Title: Re: Another question about identification
Post by: Arizoni on August 06, 2013, 11:47:25 pm
IMO, that would be worth doing.
Speaking from experience, when new parts are introduced in a design to increase strength or improve reliability they often require more room.

To keep the cost impact of the new parts from requiring other new parts, the new part is often designed so there is a minimal impact on the surrounding hardware.

Often the addition of a minor machine cut is all that is needed to the surrounding existing parts to provide the needed clearance.
This may be the case here and a little work with a Dremal tool might be enough to allow the connecting rods to clear.

Even if the interference is slight it will require some serious study of the area to make sure removing material to clear the rods won't cause a thin wall but if the thickness of the material is enough then it may be worth doing.  Just remember to remove a little more than the absolute minimum.  Moving parts and thermal expansion can cause the interference to reappear when the engine is running.
Title: Re: Another question about identification
Post by: Roger ONeill on August 07, 2013, 12:40:32 am
Hello Again,

Bare have laid one type of rod on top of another and taken measurements and the out side and inside dimensions are the same for the rods with and without the big end shells, the only difference being the bottom end bore. We actually have one set of rods that fit ( with shells) they were so beat up that we do not want to use them but they do match the rods without the shells. ERC we have done what you suggested and the interference is when the crank is just reaching bottom on the power or intake strokes or is just beginning to rise on either the exhaust or power strokes. It appears to be the bottom outside edge of the rod's bottom cap that is causing the problem. We will persist however and solve this thing.
Cheers,
Roger 
Title: Re: Another question about identification
Post by: ERC on August 07, 2013, 01:15:43 am
Hi Roger, I was thinking I wonder if you've got an Interceptor crank, it has a 3mm longer stroke but uses the same rods as the others. Don't have one to measure the width to see if it would fit in an early case or not. Was the motor together when you got it?  ERC 
Title: Re: Another question about identification
Post by: classicrider on August 07, 2013, 02:56:04 am
Maybe you could you try the mod Eugene suggests using the 42597 rods(still available from Mr H)and grind the crank back to 1.7715".You would effectively be starting off with a new crank then.You gain the clearance because the end cap is pulled in close to 1/10".
colin
Title: Re: Another question about identification
Post by: Roger ONeill on August 08, 2013, 09:03:44 pm
Hi All,

Thanks Colin, basically your suggestion is one we came up with and it is more or less what Hitchcock's said in their last note to me which arrived yesterday. Her is their response and they sent an attachment which is really quite helpful. I think it is something worth having on hand. I am having trouble with the attachment. This site will not let me add it to this message. I will try to reformat it and send it to you later. It is definitely helpful
Hitchcock's note:

Hi Roger,

Undersized rods are going to be a problem, you may need to look at standard rods and bore them to take shells. The attached may be of help
Regards,
Hitchcock's Motorcycles Ltd.
info@hitchcocksmotorcycles.com
VISIT US AT www.hitchcocksmotorcycles.com
HITCHCOCK'S MOTORCYCLES LTD
OLDWICH LANE WEST
CHADWICK END
SOLIHULL
B93 0EY      ENGLAND
TELEPHONE 01564 783 192  (INTERNATIONAL +44 1564 783 192)
FAX 01564 783 313  (INTERNATIONAL +44 1564 783 313)
OPENING TIMES 9am - 6pm (BRITISH TIME) MONDAY - FRIDAY

 

 

Title: Re: Another question about identification
Post by: ERC on August 08, 2013, 10:56:30 pm
That will be interesting if you can get it on this site. I've had to print them out and scan them back into the computer. Or save them in the computer.  ERC
Title: Re: Another question about identification
Post by: classicrider on August 09, 2013, 05:10:41 am
What i don't understand is that Mr H had new rods made,the insert type.Now we know the Rod without the inserts is identical or was back in the day,so why didn't they have some made with a little more alloy in the bearing area that could have been machined as insert free Rods.Beats me ???perhaps they just need this pointing out to them.
colin.
Title: Re: Another question about identification
Post by: ERC on August 09, 2013, 07:12:27 pm
On the new rods he's selling you also have to rebalance the crank I think. Also maybe a thing with which models are popular enough for the investment.  ERC
Title: Re: Another question about identification
Post by: Roger ONeill on August 12, 2013, 05:13:50 pm
Good Day all,

I think I have this figured out, so here is the post from Hitchcock's. We have been fooling around with different connecting rods that we have borrowed from friend. We had three different types of R.E. rods and each one has it's own problem. We have sent one last question off to Hitchcock's and we hopefully will have a final solution tomorrow.

Cheers,
Roger
Title: Re: Another question about identification
Post by: ERC on August 12, 2013, 10:21:49 pm
Nice I.D. chart.   ERC
Title: Re: Another question about identification
Post by: Roger ONeill on August 21, 2013, 04:52:22 pm
Good Afternoon all,

Well I guess that we have the final answer about the connecting rod for the 1956 Super Meteor. Here is the last note from Allan at Hitchcock's. Thanks for all of your suggestions.

Roger,

 

41719 and 41720 are the same rod, I note that you already have 41720 which fits your crank. These are the best of the Enfield twin rods and would be good to use if you can.  I would look at seeing if you could modify the crankcase to give clearance for the bolts or possibly machine the rods to allow the bolts to sit further down.

This is not something I have tried to do before, but I am guessing that there not much extra room would be needed.
Regards, Allan
Hitchcock's Motorcycles Ltd.

Title: Re: Another question about identification
Post by: rotorwrench on August 21, 2013, 07:58:30 pm
Cases with the "7T" marking are the early Trailblazer 700. There were three cases for the 692cc models. The early Meteor and the 56 to mid 57 Super Meteor case were a lot alike except no oil filter in the timing cover. The 58 models starting in mid to late 1957 had the removalble cam bearings and the late crankshaft for the replaceable bearing shells that had the triangle shaped cheeks on the outside. All the round cheek cranks were earlier design that used one piece con rods (no replaceable bearing shells). All of the twins from 58 on used the same con rods whether 500, 700, or 750 models. The 750 or 736cc have a little more room in the crankcase for the bigger crank but the crank looks a lot like the 58 & on 700 type.

If you have the earlier 55/57 Trailblazer engine then the case was set up for the round type crankshaft and had solid con rods. The 58 Trailblazer was nearly the same as the Conny except for the cams (T-Blazer used two Super Meteor exhaust cams and the Conny used the same cams as the later 750 models) and the type of carburetor. T-Blazer had the Amal 389 and the Conny had the Amal 10TT9 like the 58 Apache used. Some Connies had the twin Y manifolds and two special carbs to work on it. The Trailblazer kept the SR2 mag and the Conny went to the K2F with manual spark adjust. The 58 & later Apache engine was nearly identical to the Conny engine in the same time frame. I have one of these motors but I don't have the K2F mag or the 10TT9 carb.
Title: Re: Another question about identification
Post by: Roger ONeill on September 03, 2013, 04:18:39 pm
Good morning All,

This is just a note to let you know how we made out with the crank case problem and to thank you for your suggestions. We decided to follow Hitchcock's last suggestion which was made by a couple of you early on in thediscussion. We used connecting rods 141719 (marked 141720/a) and removed the square edges from the front and back of the connecting rods near the big end. We do not feel this would have an effect on the integrity of the rod. We also used the tapered cap bolts and reduced the depth of the bolt head by about 1/8 of its original height. Once installed in the cases there was no fouling at the bottom of the crank cases. Now all we have to be concerned about if and when we get thing running is the expansion of things whenit gets heated up.

Cheers,
Roger
Title: Re: Another question about identification
Post by: Roger ONeill on February 28, 2014, 05:55:49 pm
Good morning Royal Enfield People,

It has been a while since I have informed you about our progress with what we now suspect to be a 1956 Super Meteor. We have been working diligently and have almost reached topoint of getting the thing started. With that in mind does anyone know how many degrees BTC and fully advanced things are when doing the timing. I would rather use a degree wheel than trying to measure 3/8" accurately.  I have attached a picture of the bike so far. The tin ware is not all correct but we think it works.

Cheers,
Roger