Power to the Coil

Perfect that's it! Will also buy a compression tester today too. Now to research why I'm only getting fuel to one of the plugs. Had the bike running briefly on the left cylinder! Can't believe just how much time is going into this bike......there is no way I could sell it once it's done!

IMG_20170827_1051265.jpg
 
That is a '78-'79 carb set. The overflow pipes in the float bowls were eliminated on that carb set. If the bowls over-fill, it comes out the throat of the carbs. So, that means you have a bad float needle and seat or a bad float. Or it could just be a float set wrong. There's also the possibility you just have some dirt stuck in the float needle seat and that won't allow it to close.
 
Sometimes when installing a dry carb after cleaning, the float will stick in a low position. I always expect this to happen, usually happens about 60% of the time. I always have a piece of wood or the butt end of a screwdriver ready to whack the side of the carb to free up the float.

Scott
 
The brand is Doherty.

If you find a source Paul - could publish it here please?

Thx

Pete
 
Thanks guys, will take off the carbs later and take a look. I'm also going to print off the carb guide because fuel is not reaching the right plug/cylinder. Which model carbs do I have 5T? Pete, I've not had any joy yet, I'll let you know when I do.......
 
Yup - that's what they look like to me - BUT - 5Twins knows these carbs far better than I.

Pete
 
So I've just stripped down the carbs and I can see the float bowl gaskets need replacing as they are perishing and bits are breaking off and clogging things up. Is there a sure fire way of getting the part number for the BS38 carbs? Nothing available in the UK but cheap enough from the US, I think these may be them....
http://www.ebay.com/itm/311923482116
 
Yes, those are the ones. Do an eBay search and you may even find N.O.S. originals for about the same price. Before install, make sure all the little punched out holes have those punches removed. Sometimes they don't, particularly the one along the edge for the choke jet.
 
So I got home from work today very tired and started to clean the carbs again....despite knowing to use tight fitting tools on brass parts I still stupidly went ahead and started to unscrew the main jet, the 1st one came straight out but the other the slot sheered away! My fault entirely! I think I'll leave it in there unless it has to come out.....I guess I just hate damaging things. If I were to attempt to remove this what is a good method? Some sort of screw extractor?
 
Oiling cables - Years ago I was shown the following way to oil cables and still use it today. Take some oil and dilute about 75/25 with petrol and put it in a drinks bottle. Wrap some cloth very tightly around the end of the cable and then jam the cable in the bottle. Prop the bottle up and place a drip container under the other end of the cable and leave it overnight. The thinned down oil will slowly seep through the cable. The next day remove the cable and install. The petrol evaporates away leaving a nice oil coating in the cable.

For speedometer and Tachometer cables I just pull the cable out then feed it back in with several very generous squirts of motor oil.
 
So today I received a basic pair of rebuild kits for the carb bowls, just finished them, got them on the bike a it started 2nd press of the button! Actually sounded pretty damn good considering it only had the headers on. Now, am I missing a 2nd idle stop screw?

see photo:

..IMG_20170901_1709271.jpg
 
No, there is only a stop/adjust screw used on the left carb. The right carb is controlled/held by the linkage. Adjusting the left screw will move/adjust the butterfly plate in both carbs, left carb with the screw, right carb through the linkage. Both carbs are made from the same casting, that's why that screw tab is on both.
 
Wow - bike looks nice and that is the cleanest shop floor I've EVER seen Paul!

Your Mom would be so proud. ;)
 
So I got home from work today very tired and started to clean the carbs again....despite knowing to use tight fitting tools on brass parts I still stupidly went ahead and started to unscrew the main jet, the 1st one came straight out but the other the slot sheered away! My fault entirely! I think I'll leave it in there unless it has to come out.....I guess I just hate damaging things. If I were to attempt to remove this what is a good method? Some sort of screw extractor?
Cut the slot deeper, there's a trick. ground from a windshield wiper stainless strip. watch out for the threads on the bowl drain...
Bs34jet (2).JPG
 
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