Other than Amal carb questions

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powerdoc

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I looked at Amal's web site for carb rebuilds and my slides look like the ones that they say need replacing, after only 5600 mi on the bike. Mikuni's are only about $100 apiece but I notice that they require a rubber manifold adapter (perhaps if the Amals were mounted with rubber they wouldn't self destruct = just a thought) and the kits are about $500 for a pair with accessories. What else is included to warrant the extra money?
 
I think you're taking your life in your hands discussing this at the moment !!!

Heehee.
 
Perhaps true but it's beginning to get a bit chilly in this hemisphere so a little fuel on the fire will be warming! It's really amazing though about the rubber mounting. I had a 1958 Alfa Veloce with twin Webers that had rubber mount back then. Why didn't the Brit bike manufacturers do the same thing? I've never been on one that wasn't a butt-massager at idle and low speed and didn't they realize it was just slamming those slides against the body; and once it starts to wear it's going to wear faster and faster.

This bike I'm redoing isn't going to be primary transport but rebuilding at less than 6k on the clock is ridiculous!
 
There is one avid Commando rider in this forum that recommends rubber mounting Amal carbs. So you are saying there are wear marks on the slide? Does it rattle in the bore?

Russ
 
Before I replace them I'm going to actually mic them and see how far they are from spec but I want to remove the cables first, and since I'd never done that I had to find out how to do it! My workspace is in the dark right now so I'll have to wait for tomorrow. It has linear striations and a darker banding at the upper end of the slide.
 
Gee wiz Doc,... "linear striations", ease up, what does that mean, some of us are only simple folk, well mainly simple. hehe.
You have raised a very good question, possibly argued before.
Rubber mounting might be a very good idea, but as with most Carby mods on Commandos, distance from the manifold to
the air box is the problem, if you want to keep things looking somewhat original.
Mikunis have stood the test of time.
Jims PWK set up is neater and is getting good reports.
Your Amals can be sleeved quite cheaply, and will work again.
There are new Amals coming onto the market that should be better than the old ones.
If you stick with Amals, do yourself a favour and fit some Allen head screws to the Float bowl and
the top of the bodies, then you can work on them (the carbies), with out having to remove them from the bike.
Good luck with your decision.
AC.
 
powerdoc said:
I looked at Amal's web site for carb rebuilds and my slides look like the ones that they say need replacing, after only 5600 mi on the bike. Mikuni's are only about $100 apiece but I notice that they require a rubber manifold adapter (perhaps if the Amals were mounted with rubber they wouldn't self destruct = just a thought) and the kits are about $500 for a pair with accessories. What else is included to warrant the extra money?

Sudco lists the carbs for $104, manifolds for $210, and the rubber adapters for $45/pair. That adds up to $463, so if the kit includes much of anything else, like throttle, cables, or air cleaners, it starts to look reasonable. If not, you're better off just to buy the bits separately. You'll need air cleaners, because the Mikunis splay out to the sides to fit, so you don't get to keep the stock air box.

Ken
 
Body wear is the bugbear . Thats wot the other bits bolt onto . If the bodys are fine , why , a 10 yr old could . . .

If the slide bores are worn in the body ? its as the material is a bit susss, good air filtration helps, as does
removeing the choke. Big score marks , several , are not unlikely unfortunately. If not present the units are serviceable .

The biggest larf is if youve got the plastic cable slide junction . Virtually garbage , the slide cocks so the action at the carbs arnt progressive.
Theres a ancient long chromed brass with ( longer ) steel slider / junction block .Which if clean and oiled will give smooth even action .
The choke mechanisms are a seperate chapter in the same book , best discarded and tops plugged . if youre not a commutor .

Changeing to a Dual Cable twist grip , with smooth cable runs and the individual adjusters positioned at the centre of a straight run , taped or
cable tied ( Arg , Thats wot theyre for ! :wink: ) against a pad so as not to rattle or fret / chaff paintwork , and youll be convinced that even
the quality metal junction assembly is an impedement to smooth and accurate throttle action , and excess weighting , due to double the individual
load through the single cables curve from the handlebars .

Also the gearing of the standard twist grip is low to diquise the friction , requireing excesse wrist flexure , if possible , stop to stop ( shut to fully On . )
Sitting on the machine , Roll the throttle to fully open with Yr left hand. Grasp with the right at a comfortable ' fuly open ' position, and maintain grip .
WITHOUT MOVEING on the machine ,
Rolling it shut without releaseing , will it go near the idle stop . whoops , oh well , it stops excessive acceleration and resulting consequences whilst
becomeing familiar with the machines operateing characteristics .
A Surprise to learn you need the elbow down near the knee fully open if gripped from
arm out wrist flat. And good fun seeing what she actually does go like fully open . :shock:

A number of features were possibly incorperated to maintain the coustomer base, hitting things endagered the pilot .Like current monkey rider positions
which encumber accurate control of the machine ., by hanging the driver in the wind like the washing .
agreed weighting footrests assists line holding ,steering with the feet, particularly if your arms are folded . :wink:
but generally Commando's benefit from a securely
placed rider , and finger tip solenoid like operation of Controls. Particularly the Gearshift , Forceing the mecanism inhibits actuation and mangles internals.

Part of ' gear change tichnique ' is being familiar with the ' free off ' point in clutch engagement / disengagement .Ordinarily the lever is not pulled to the bars , but to the disengagement poit , then the gear selector operated , and lever released . in one continuos sequential motion .Why then there's . :oops: :P
 
AussieCombat said:
Gee wiz Doc,... "linear striations", ease up, what does that mean, some of us are only simple folk, well mainly simple. hehe.


I'll post a picture when I get it off the cable.
 
generally Commando's benefit from a securely
placed rider , and finger tip solenoid like operation of Controls. Particularly the Gearshift , Forceing the mecanism inhibits actuation and mangles internals.

Amend to staying centered on un-tamed C'do being pressed into long held accelerating turns. A fast off throttle twist is rather more important than its fast on WOT feature. Just takes a tiny little clutch squeeze and throttle sense to snick easy smooth gear changes up or down, often its automatic when combo of loads and rpms allows simple clutchless shifts at merest thought of toe tap.
 
rvich said:
There is one avid Commando rider in this forum that recommends rubber mounting Amal carbs. So you are saying there are wear marks on the slide? Does it rattle in the bore?

Russ

I'm another.
 
Yes indeedy . I still cringe from ' a friend ' who was steering my Commando , insisted I rode back .
The large steel capped clodhoppers and the ' punch the gear lever ' were grauching the box on
almost every shift . More than my delicate sensitivities could bear .Positively Painfull & traumatic .
I become unsettled and cant sleep Each I remember it .

I know a bit of body language can be usefull , But Mike Hailwood never bothered , whilst leaveing
allcomers in his dust trail . Be intresting to see his technique for the Honda 500 six .Commonly
described as the ' Honda Handling Horrors ' . but I degresss .

Now , a real sports bike has someone holding the handlebars all the time ( as well as the feet on the footrests :P )
So an IDLE as far as the carburation goes , is not only unnessesary , but Doesnt slow you down . :shock: :?
Setting the throttle stops even , but with the Carb slides positively closed , will get superior Engine Brakeing .
As you lean into a bend to pick third at 90 mph , and nail it .Works at slower speeds too . . . :D

However , it is uncouth and loutish to sit and blip the throttle / revs at standstill , other than at start up . :P
Practise with the thumb resting on the cable holder will ensure a practised low idle , so the engines doing the
gentle steam train like ' chofff chofff ' Era of low speed opperation .

The old grand prix idle of nang nang nag , was to catch the lower end of the cam and keep it running , whilst stationary
and slideing the clutch to keep the engine ' on the cam ' in hairpinn bends with a 4 speed close ratio gearset .

Primarilly it was the two stroke geniuses who did the blip blip blip , nang , nang , nang , on the start line , that all the RD 350s emulated . :roll:

However , a gentlle brurp type ossilation is permissable and not nessearilly in bad taste . :P :)

The rom rom rom CRUch at the lights though induces the horrors first mentioned in this particular spiel .and has me shakeing my head in wonder
as to exactly what is attempting to be achieved . :cry: :|
 
This thread started as an informatory one about what was included in the "other than Amal" dual carb kits to make them hover around the $500 mark. Is it add the parts together and add some more profit?
 
With the carbs from Jim Schmidt you get the right jets for your bike. (Or so I have read on this forum)

That is not a small thing. There is a difference between getting a different carb set up to fit and getting one to work.

Now if I could just find a photo of those rubber mounted Amals....

Russ
 
powerdoc said:
This thread started as an informatory one about what was included in the "other than Amal" dual carb kits to make them hover around the $500 mark. Is it add the parts together and add some more profit?

I have them and to some extent i was comfortable knowing that i was paying for some R+D. There is another thread going on in conjunction to this one about single vs duel carbs.

I thing these carbs breach the gap from low end torque and top end performance. Flatsides meter better and could be considered, at least by me, as the best of both worlds.

I have a cam that is suppose to like the mid to upper range, and believe you me, it does. With these carbs I attain a good pull off the bottom as well.
 
powerdoc said:
AussieCombat said:
Gee wiz Doc,... "linear striations", ease up, what does that mean, some of us are only simple folk, well mainly simple. hehe.


I'll post a picture when I get it off the cable.


Well guys, here is the offending slide from one of my carbs that started my whole rant about induction and various carbs:

Other than Amal carb questions


It looks like it's been rattling around pretty good in the bore. It calipers out to 1.371" with about .004 clearance. Is that in spec?
 
powerdoc said:
powerdoc said:
AussieCombat said:
Gee wiz Doc,... "linear striations", ease up, what does that mean, some of us are only simple folk, well mainly simple. hehe.


I'll post a picture when I get it off the cable.


Well guys, here is the offending slide from one of my carbs that started my whole rant about induction and various carbs:



It looks like it's been rattling around pretty good in the bore. It calipers out to 1.371" with about .004 clearance. Is that in spec?

I must say, that slide looks to be on the fair to good side. Nicely wore in so to speak and not really wore out. Anyone want to back me up on that? Semichrome the bore and remove any scratches off the slide. Run it!
 
Well, if I have to lap the bores I guess it'll be another gasket set as I'll have to ultrasound the body to get the grit off. Any other suggested things to do while the carbs are apart or just follow Amal's instructions? What blasting material is best for the outside to get a nice finish?
 
powerdoc said:
Well, if I have to lap the bores I guess it'll be another gasket set as I'll have to ultrasound the body to get the grit off. Any other suggested things to do while the carbs are apart or just follow Amal's instructions? What blasting material is best for the outside to get a nice finish?
Soda. You can make your own blaste. Search "soda blaster" and you should find it.

You might want to look into drilling out the pilot jet and going with a scew in type. It's not a very big job. 1/8 drill just deep enough. Tap and drill to 10-32. Get a throttle stop screw and cut it off. Add fresh oring on the stop screws and your good to go. No more gunked up circuit. True up all mounting surfaces while you are at it.

http://www.aircooledtech.com/tools-on-t ... a_blaster/
 
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