Hitchcocks Forum

I have acquired a 700 Meteor which had been restored but left idle for many years. After the usual cleaning up it started, but it runs very erratically. I have thoroughly cleaned the carby which is an Amal concentric 626. The main jet is a 190 and the needle jet is 106 and I have replaced both needle and jet with a good spare. I have tried all 3 slots on the needle which makes no difference. The mixture screw doesn't improve things either. The points and leads are new. The plugs are new. The distributor cap is new and the timing is spot on at a little after TDC. (Strange but that's what the book says).I have moved the timing back and forth by turning the distributor to no effect except slowing the motor. I suspect this is not the correct carby for this model so is there anyone out there with a similar Meteor Twin who can tell me how their bike is carburetted.The compression when tested with a gauge seemed to be around 35 pounds each side. Pouring oil in the plugholes does not change this. The plugs are quite black and the intake manifold does not appear to be leaking air. What could cause it to run so rough when it starts so easily. The mufflers are free flowing and quite loud and the air filter is just a POD type.Any ideas?

Original carb would be a pre mono,ancient carb and the concentric should do a better job if it's not worn to much,they come out about 1967.
Really first thing to do is confirm air jet is not blocked,problematic on this type of carb.Float height correct?
Try turning off the fuel while it's running,sometimes they can clear up while they lean up a bit.there's more but that's a start
cheers
colin

This might help you Creaky; I have a Constellation so pretty similar to yours. A 626 is a bit small, I have a 928 fitted with the following: 3.5 slide, 250 main jet, 106 needle jet, needle is in the 2nd clip. Anyway in my infinite wisdom i decided to fit an air filter, whats the harm in fitting an air filter, filtered air is good was my reasoning... the bike ran like a pig! I removed the air filter, fitted the short standard amal bellmouth and hey presto the bike ran like a dream

I ran a Meteor for many years (it is now in Hitchcocks collection) and I found that even after an expensive distributor rebuild I couldn't get it to run properly. I had an inkling the rotor arm was the wrong one but trying different ones (there are loads of different ones for different Lucas applications) didn't seem to help. Then I found the site of The Distributor Doctor who provided the correct rotor arm made to the proper specification. Problem solved. You should also make sure the bob weight springs are in good condition, again the Distributor Doc can provide them. And he's a really helpful guy as well.

REgards, Mark

I don't know if this is of any interest, Mark M, but some parts in the distributors that stick up from the dynamos are the same as in the Crusader ATU's and also the Ariel Square Four. I am not sure about rotation off the top of my head, but this might broaden horizons for some spares, as I think some should be interchangeable. Regards, Paul.

Does the carb have a petrol inlet filter? Could be worth checking for blockage. A new coil would rule out another possibility.

Marko, I will be replacing the carby with a 928 to be sure. How have you jetted yours? Mark M, I have checked out the Dist. Dr. and asked for info about my rotor which is a 000052 but it looks ok. I will pull the dist apart if the new carby does not fix the problem. Also I will replace the condenser.Ed, No there is no fuel filter and the fuel level is right.I have no spare coil to substitute, only a 12 volt one. My coil test fine on the bench with a primary resistance of 1.5 ohms and secondary of 6000 ohms. (6000 sounds a bit low. Does anyone know the resistance of a 6 volt coil?) Thanks all. I will keep you posted.

Creaky, rotor arm should be 400052, I assume you have a typo in your text? There are some very poor rotor arms out there, read the Dist Doctor site for explanation. Paul, there isn't much common between the Square 4 distributor and the Enfield one, apart from the body, only small parts. In my experience the dist is quite tolerant of wear but the rotor arm, bob weights, springs and cap must be good. There are also rubbish pattern dist caps out there too!

REgards, Mark

As extreme solution, only if all else fails, considering the price!



http://www.bt-h.biz/md2r---magdyno-twin ... o-18-p.asp



A.

Adrian, Wow 730 pounds for that. Thanks but I think I will replace a few more things first. Mark, my mistake. It only has 52 (no zeros)and an arrow showing rotation direction on it. I got the other zeros from the Dist Doc site. I'm still banking on a crook carby and waiting for Marko to tell me how his 928 is jetted. Come on Marko, I'm ordering one today.