BSA 1970 650 Lightning chopper

[Guest]

Can I use the O-rings provided in the new kit on this build I was not sure if they would melt since the carbs bolt to the head?

[Guest]

I just ordered some heat spacers going try them on face of head then carbs to the spacer.

[Dougtheinternetannoyance123]

If you use a good quality viton or Nitrile O ring no issues, Heat spacers help regardless. Depending on the
type of spacer, some use a gasket some dont. The original spacers were a fiberboard material, I can post a
picture if you like, But many suppliers sell a paper-composite spacer and they dont need a gasket.

There is a little bit of a trick to the o rings. Most knuckle draggers over tighten and in due course warp the
carb bodies. The trick with an O ring is only to nip it up, NOT mash it down. The originals also used small O ring
insulating rubber pucks on the carb studs as well. Most people are confused by this and discard them.
Research the right way. (Factory workshop manual and parts book) Myself I will use the crappy pot metal
Amals on restos but I detest them and their shittiness. I like Mikuni VMs personally but the JRC-PKW flat slides
are excellent and cheaper than the Amal junk.
Just my opinion.

[farmall]

There is a little bit of a trick to the o rings. Most knuckle draggers over tighten and in due course warp the
carb bodies.

Oh yes they fucking do!

My late mentor even figured out a way to straighten them (because flattening the flange doesn't save the bore) with a plate and long bolts to pull the ears back. It worked but I've never done it. He verified with a machinist straight edge.

They make Amal Premiers of aluminum but I've not looked into it since other than the cool tickler I've no reason to care.

Speaking of pot metal (Zamak or other zinc cheap shit) I found out Amals dissolve in phosphoric acid solution many years ago when dipping some corroded bodies. It was pretty neat as it exposed the internal passages.

Before you install any O-ring, measure it with a caliper (ID, OD, thickness) so you can order bags of Viton or Buna rings for next to nothing. Then before you forget, order some via Ebay etc (or industrial suppliers if necessary) and stash them with your carb stuff.

[Guest]

Yes I got this now I ordered the Phenolic Spacers and the O-rings the carbs are pretty much new the old guy that had the bike lost use of his arms and He had got them and I dont think he knew alot about the spacers He dont even own a computer. But I put some kits in them and slides work great. I like the mikuni way better myself but this is just a project work of art bike I may just cruze it a few times each summer. Its just bad ass old school chop Like my HD chopper I only do old school even my dirt bikes are all 70s LOL love the Suzuki TS185s they rock. Thanks for the input Im hoping it will work out I put some drag pipes on her the other day and shes pretty loud.

[Guest]

10-4 will do.

[Dougtheinternetannoyance123]

Yes I got this now I ordered the Phenolic Spacers and the O-rings the carbs are pretty much new the old guy that had the bike lost use of his arms and He had got them and I dont think he knew alot about the spacers He dont even own a computer. But I put some kits in them and slides work great. I like the mikuni way better myself but this is just a project work of art bike I may just cruze it a few times each summer. Its just bad ass old school chop Like my HD chopper I only do old school even my dirt bikes are all 70s LOL love the Suzuki TS185s they rock. Thanks for the input Im hoping it will work out I put some drag pipes on her the other day and shes pretty loud.

Hah! hope for the future! I got a couple younger guys (20-30) I try and help out, pay it fwd, but funny you mention the Suzi TS185. I got a early 70s TS250, Mines blue and white. Great little bike. Traded a Triumph Bobber frame for it to a school teacher into customs. He admitted he got the Suzi for free from a neighbors estate. The family was pushing it to the curb for trash-scrap. I serviced it and its pretty nice. Good fun!

Theres a lot of tricks to the Amals, tons of material out there on them. Biggest is the idle air circuit. It comes in off the side with a screw adjuster against a 20 thou jet that clogs up often intersecting with the front to back air bleed near the Aircleaner opening. Proof that with carb spray cleaner and a air nozzle. There is a guitar string or accupuncture needle that works good for clearing it. Built up scale use a commercial sonic cleaner to clean the hidden invisible nasties.

But the original floats dont like modern fuel so need to get the new type floats. Dont leave it sit with fuel in it. get the drain style float bowls (Small screw in drain plugs) There also a trick to getting the cables nice and smooth. I use a spiral wrap and then shrink wrap over them so it does not kink or hang up. (Wrap about 4 inches so it makes a sweeping radius)

Tuning by ear is an acquired art but it can be done. I also love to use a vacuum gauge with a inline damper and I have an old school snap on carb mixture reader that sticks a probe up the pipes.

[Guest]

Great info I do have the drains in the bowls I just thought I would use them since they came with the bike I will give them a try when I get the rest of the stuff. I had it sounding ok at one point had a good chop seems cold natured as hell but when warms up idles fast Im thinking some air leeking with them paper gaskets and I did not use the 0-rings that came with the kit. They are 930s and I think I got them clean but not sure on that one spot you were talking about I saw another post somewhere about the wire. I have a crappy vid I can post if you want to hear it. I will try to upload it here. But yes Im really liking the 185 would like to get a 250 sometime I have a 73 and 74 185 and a 71 TC90 got it cheep cool little bike has a high and low range. I may try to run the wire in there when I take them off again to add the heat sheilds and o-ring. take care.

[Guest]

This is the ones I have do you think the wire will work on those models ? the adjustments are side by side on them and not on left and right like the photo? Also would I need to notch this model like the last photo shows? thanks

[Dougtheinternetannoyance123]

[ATTACH=CONFIG]103319[/ATTACH] This is the ones I have do you think the wire will work on those models ? the adjustments are side by side on them and not on left and right like the photo? Also would I need to notch this model like the last photo shows? thanks

Thats a clean looking carb, its got the extended tickler so thats a good sign. Here is how to proof it. Take a can of carb clean, use the little red straw. Or,, if you have a air powered squirter with solvent, not many have that. But remove the float bowl. theres a small hole going up INTO the carb body, IIRC its towards the front near the float pivot. Thats a passage to pass fuel thru. Now... on later carbs that passage is threaded. On unit singles (BSA 441 B25, T25 Triumph) They dont run the jet inside the air passage, its a screw in 20 thou jet.

** If the jet internally is damaged, clogged or beyond repair, drill it out and just use a screw in jet ala the unit singles.

Anyrate,,, while apart, spray in the air bleed holes at the inlet going straight back. You SHOULD get a dribble into the main throat, you should also get spray into the float bowl area from that other hole. Now.. remove the air mix screw. Put a gloved finger over the air bleed holes at the inlet. Now squirt thru the mixture screw hole. Again, you should get a good flow out the bottom into the float bowl area and a good sized spurt into the main passage.
Now,.. lastly Cap off the air bleed holes again AND the hole into the float bowl area. Now jam that straw into the air bleed hole and give a good squirt. Where the slide comes down, theres a ring in that main passage. There should be 2 tiny holes. One on either side of the slide. Look very carefully.. This final squirt you should see both holes spurt with a vigorous spray out of each hole.

**IF NOT** Then you got scale, dirt, grunge, sludge or something in there. But ALL those passages have to be totally clear. Carb cant meter fuel and air if that passage has even a slight issue.

I have a better diagram, but I am tired and going to bed. Ill try and find it tomorrow and post some pictures as well.

Theres some good tutorials on balancing them both as well. MAP cycle had a good write up, as well as a good tutorial on Mikunis and race tuning. Also visit victory library.

http://victorylibrary.com/CONC.htm

Ahh,, sh*t I knew it was somewhere,, BUSHMAN is da Man!
See: http://www.jba.bc.ca/Bushmans%20Carb%20Tuning.html

He has the diagrams I was looking for, Study that!

[Nanonevol]

Here's some cutaway photos. First one from Bushmans, second from Vintage Bike

[winddrifter]

great info going dive into this I was locked out of this forum for some reason but got back in now. thankx

[winddrifter]

Looks great going check it all out thankx

[Nanonevol]

Now that I think of it---
That is a clean looking carb you pictured. I wonder if it is a "Premier" or a new Wassell Premier.
If it is it will have a removable pilot jet on the opposite of the side pictured. A great improvement.
If this is the case you can disregard the posts on cleaning with a piece of wire.
Will also have anodized slide and stay-up float, etc.

Don't worry about notching the float bowl for increased flow unless you plan to ride WOT for extended time.

[winddrifter]

No mine are the old style carbs that was just a photo I used. I think Im good to go now waiting on parts to arrive before I tear down if this fails going to the new style or a Mikuni. Im going post another thread on some angled extenders for the carbs sortly like old webco style know of any place I can buy them? Photo is not correct just shows sorta what Im looking for.