Carby gasket Bendix carby

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Carby gasket Bendix carby

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Hilly
22 days ago

Such a good thread, I'm glad you came along Merv, has been a learning curve for me 👍
Steve has lots of tricks up his sleeve 😁

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obisteve
21 days ago

Merv, it is a great thread, I'm glad you're onboard too.
And Hilly, I had to find a better way. There I was in 1971 with a POS C15 BSA, I reckon it was BSA's worst bike ever. The service notes told me to determine points opening by being able to pull a cigarette paper from between them; and I didn't smoke. Read about the radio method in a mid 70's Yank bike mag and used it until I bought a timing light during my Norton days.
It works better if you have a copper wire cored HT lead. I have one in the shed for timing purposes.
And no officer, I don't run it on the road like that, why that might interfere with people watching TV, and govvys of all stripes won't allow that. Why, if people didn't watch TV they won't be able to absorb the ads, and they might stop consuming and start saving. Shit, that might crash the economy!
Or maybe I'm just an old hippy that lived in the bush with no TV reception for 40+ years.

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Merv
21 days ago

Quoting obisteve on 11 Nov 2025 08:59 AMedited: 11 Nov 2025 09:02 AM
Merv, it is a great thread, I'm glad you're onboard too.
And Hilly, I had to find a better way. There I was in 1971 with a POS C15 BSA, I reckon it was BSA's worst bike ever. The service notes told me to determine points opening by being able to pull a cigarette paper from between them; and I didn't smoke. Read about the radio method in a mid 70's Yank bike mag and used it until I bought a timing light during my Norton days.
It works better if you have a copper wire cored HT lead. I have one in the shed for timing purposes.
And no officer, I don't run it on the road like that, why that might interfere with people watching TV, and govvys of all stripes won't allow that. Why, if people didn't watch TV they won't be able to absorb the ads, and they might stop consuming and start saving. Shit, that might crash the economy!
Or maybe I'm just an old hippy that lived in the bush with no TV reception for 40+ years.

Jeez, don't tell me any more! I just got out the soldering iron, some clips and some old fashioned plug wire and made myself a couple new plug leads!
Somewhere in my tool maze I have a device that's made for the aircraft industry that beeps and lights up like a Xmas tree for checking timing, specially for twin points. Maybe because light aircraft have twin magneto's? I've never used it because I could never understand the instructions. The radio trick reminded me of it. Looking forward to trying the radio some time tomorrow. Finished with the medical profession this arvo and still living, so I'll be back into the Ironhead tomorrow. Back with good news I hope. And Hilly, I've enjoyed the education in this thread as well, and thank everyone who responded.

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Merv
20 days ago

Finally got back to it. Installed the correct cam/rotor they sent me and retimed it statically to fire with cam wound to advanced position at the line on the flywheel. Then checked the idle position however the light lit well before the single dot appeared. The cam has a flat side that when turned, hits a pin, preventing it from turning further, and I suspect the plastic magnetic rotor has a little more meat on it than the original steel cam, limiting it's travel. Tried to use the clear plastic plug and was a total waste of time. Still to use your radio method Steve.

Larger pilot jet (#35) has given me back idle mixture adjustment so I went for a ride. No backfires and actually pulled to my great enjoyment, however wrapping the throttle in a higher gear to test power (not speed) saw it popping and dying so I will move to the next size main jet before next test. Idle and intermediate throttle responded well, but didn't seem to have the power it should so I will ever so slightly advance/retard timing during tests until I reckon I have it right.

Very happy with this old bike - it seems to grow on you. Starting to wonder if I need any of the others. It idles so slow that I think it will stall next rev, but it keeps going. Eager to learn as much as I can about it. Do you like the hand change I made for it?

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Hilly
19 days ago

I dunno about ironheads but the evo needs 900 or better at idle for oil circulation, gear stick looks the goods, at least yours is going, I keep pulling bits off mine 😁

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Merv
19 days ago

Quoting Hilly on 13 Nov 2025 09:28 AM
I dunno about ironheads but the evo needs 900 or better at idle for oil circulation, gear stick looks the goods, at least yours is going, I keep pulling bits off mine 😁

Never thought of that. But oil pressure must still be ok as oil light doesn't come on? Why are you pulling bits off it?

Hilly
19 days ago

Quoting Hilly on 13 Nov 2025 09:28 AM
I dunno about ironheads but the evo needs 900 or better at idle for oil circulation, gear stick looks the goods, at least yours is going, I keep pulling bits off mine 😁

Quoting Merv on 13 Nov 2025 10:06 AM
Never thought of that. But oil pressure must still be ok as oil light doesn't come on? Why are you pulling bits off it?

Fixing things that need fixing, it's slow though, I don't have much fuel in the energy tank, pretty sure you understand how that works but it'll be worth it when I get to ride it 😁

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Merv
19 days ago

Hilly, I wish I was a little closer to help you mate. We could swap some yarns, and maybe I'd even learn something.

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Stuart
19 days ago

Merv - yes - gear shifter looks the goods. Did you turn the handle yourself?

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Stuart
19 days ago

Quoting Hilly on 13 Nov 2025 09:28 AM
I dunno about ironheads but the evo needs 900 or better at idle for oil circulation, gear stick looks the goods, at least yours is going, I keep pulling bits off mine 😁

Quoting Merv on 13 Nov 2025 10:06 AM
Never thought of that. But oil pressure must still be ok as oil light doesn't come on? Why are you pulling bits off it?

Quoting Hilly on 13 Nov 2025 10:20 AM
Fixing things that need fixing, it's slow though, I don't have much fuel in the energy tank, pretty sure you understand how that works but it'll be worth it when I get to ride it 😁

Nothing wrong with slow, Hilly. I long ago came to the conclusion that I should only work on stuff when my head is in the right place. Otherwise I tend to build my personal problems into whatever I'm working on. Does mean that simple jobs can take a long time sometimes though :-)

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Hilly
19 days ago

Thanks fellas, enough about me, hope you get the jetting sorted Merv, you have certainly covered some ground with this old girl 👍

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Merv
19 days ago

Quoting Stuart on 13 Nov 2025 07:19 PMedited: 13 Nov 2025 07:19 PM
Merv - yes - gear shifter looks the goods. Did you turn the handle yourself?

Nah. Cheap as chips at Repco, but rest is home made. Whole thing works a treat and my wooden leg can sit peacefully on the foot board cos there's nothing left for it to do. Bit harder to find neutral tho.

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obisteve
19 days ago

Quoting Merv on 13 Nov 2025 07:37 AM
Finally got back to it. Installed the correct cam/rotor they sent me and retimed it statically to fire with cam wound to advanced position at the line on the flywheel. Then checked the idle position however the light lit well before the single dot appeared. The cam has a flat side that when turned, hits a pin, preventing it from turning further, and I suspect the plastic magnetic rotor has a little more meat on it than the original steel cam, limiting it's travel. Tried to use the clear plastic plug and was a total waste of time. Still to use your radio method Steve.

Larger pilot jet (#35) has given me back idle mixture adjustment so I went for a ride. No backfires and actually pulled to my great enjoyment, however wrapping the throttle in a higher gear to test power (not speed) saw it popping and dying so I will move to the next size main jet before next test. Idle and intermediate throttle responded well, but didn't seem to have the power it should so I will ever so slightly advance/retard timing during tests until I reckon I have it right.

Very happy with this old bike - it seems to grow on you. Starting to wonder if I need any of the others. It idles so slow that I think it will stall next rev, but it keeps going. Eager to learn as much as I can about it. Do you like the hand change I made for it?

Hey Merv, agree with the others who reckon it's a great looking bike.
When you tried timing it at the idle position (TDC flywheel mark) and it fired early, did you still have the magnetic rotor locked at the 45° advanced position?

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Merv
19 days ago

No Steve, was turned all the way to the right, springs in advanced unit fully relaxed. Suspect the amount of free rotation of the electronic apparatus I bought is less than the original steel cam, and might get a chance to do some measuring today. I watched a Utube a couple weeks ago where the guy pulled the pin and allowed full movement of the advance unit, but I'm not yet game to try that. Pin must be there for a reason, tho I'm getting a very small band between idle and advanced. No too concerned tho, as suspect advanced is the important setting. Will come back if I have measurements.

Merv
19 days ago

Don't know if you can follow my rough workings, but I make the measurement from the center of the bolt hole to the edge of the flat to be .2425 on the plastic rotor, and .2250 on the steel cam. And a rough measure across the width of each flat gave me just .300 on the plastic flat compared to .350 on the steel. So if I took a fine file and took .0175 off the plastic flat, I may recover the movement of the advance mechanism I need for correct timing on both flywheel marks.

What does this prove? Probably contributes to the reason the same style of unit from the local HD dealer is north of $500, while this one cost me around $80. Will let you decide which one's the best value.

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Hilly
18 days ago

I think you are all over it 👍

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Merv
12 days ago

I'm still not settled with this old girl yet, as just when I think I have got it right, it goes all crazy again, and I think it has something to do with how hot it gets. So, I have come to the conclusion that it has to be sucking air somewhere. I replaced the O rings in the manifold when I put the carby kit in the old Bendix, however it seemed such a flimsy setup it was hard to have confidence in the design. So this time I am making sure to eliminate the manifold as a problem. My local parts guy supplied me with two hi tech sealing rings (wish I'd asked what they were called) guaranteed to seal anything, and you can see in the pics that they are squarish with elongated ridges on the inner, outer and both side surfaces. Cost $14 each and not cheap, but worth every penny. A comparison of the profile compared to the O ring is in about the 3rd. pic. Very easy to fit, as I stretched them over the outer area of the manifold where the clamp rests, held the manifold in position and simply slid the seals into the channel between the manifold and the barrel. They are a tight fit, and being proud will still compress, filling the gap even more when the clamps are tightened. I now just have to get my square plus small spirit level to make sure I have the carby face exactly vertical before retightening. Love the sound of this old bike, but every time I start it my two dogs race into the house to hide, trembling, so reckoned I won't start it again until I can work out how to quieten it down a bit. But reckon when I get these clamps up tight tomorrow and the Mikuni back on, I won't be able to resist it. Will let you know how they go.

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Hilly
12 days ago

Floating seal? I've used similar fixing diggers years back, hope that's it for you Merv, my dog don't like the bike much either 😁

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Merv
11 days ago

Quoting Hilly on 21 Nov 2025 07:44 AM
Floating seal? I've used similar fixing diggers years back, hope that's it for you Merv, my dog don't like the bike much either 😁

Not sure these are a 'floating seal' Hilly. Just googled them and says two steel rings held together by rubber. No steel in these, just rubber. Otherwise I would not have been able to stretch it over the flange. If describing it, I would call it a squarish O ring with ribbed surfaces. Then again, I've been proven wrong many times today alone.

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Hilly
11 days ago

Different animal for sure Merv, been awhile.

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Carby gasket Bendix carby

Carby gasket Bendix carby

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obisteve

Merv

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Hilly

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obisteve

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