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Discussion Starter #1
After a year...started my motor after a total rebuild by me!
Motor has a new Pazon ignition and a new set of AMALS.

Finally..after many kicks I got the motor to start..by lots of tickling
and full choke....in my garage which is around 60 degrees. Did the usual oil tank return check..that was good. HOWEVER...bike will not run unless on full choke. This is sitting still..reving the motor between 2500 and 3500....for a couple of minutes. I shut it off after that to avoid getting motor too hot. Restarting even after just a couple more minutes requires more tickling .

Obviously something is wrong with my new carbs. I did a float level check before I put carbs on..and made sure main jets were tight. I wouldn't think the dreaded " blocked " pilot jet syndrome would cause this?

Any hints?
 

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Discussion Starter #4
slides are 3.0's

Carbs are 30mm...slides are 3.0's.... this isn't a case of poor
throttle response...it flat won't run...in neutral with no load on it.

How warm does the motor have to get to run without the chokes all
the way down...although I think that is not the issue...some guys don't even have chokes.
 

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Discussion Starter #5
float level

I held the tabs down and saw where the edge of float was.
Now that I have gas tank on...worthwhile pulling float bowels off,
turnng fuel taps on and watching how high fuel rises in the bowels?

I seem to remember that it is supposed to almost over flow the bowls?
 

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After a year...started my motor after a total rebuild by me!
Motor has a new Pazon ignition and a new set of AMALS.

Finally..after many kicks I got the motor to start..by lots of tickling
and full choke....in my garage which is around 60 degrees. Did the usual oil tank return check..that was good. HOWEVER...bike will not run unless on full choke. This is sitting still..reving the motor between 2500 and 3500....for a couple of minutes. I shut it off after that to avoid getting motor too hot. Restarting even after just a couple more minutes requires more tickling .

Obviously something is wrong with my new carbs. I did a float level check before I put carbs on..and made sure main jets were tight. I wouldn't think the dreaded " blocked " pilot jet syndrome would cause this?

Any hints?
It seems to me that it is running too lean. So it's not getting enough fuel or it's getting extra air.
Have you checked for air leaks between the carbs and the intake valves? Specifically, is all good with the O rings between the carb flanges and the manifolds? Have you tried spraying WD on that area to temporarily block air leaks?
Mr Pete would recommend against running a new motor with no load for any length of time.
 

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It seems strange for two carbs to exhibit the same fault. Is there a good strong flow of fuel from the taps and is the fuel cap breather clear? Is your battery in good condition and fully charged?
 

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I seem to remember that it is supposed to almost over flow the bowls?
The fuel level should be 0.170"-0.240" below the top of the bowl.The needle-jets should be 106 (cross-drilled).Check the pilot jets.If they are pressed-in type,a small diameter wire (0.016" or less) should go through the jet and 1-1/2" into the carb body.

I bet the mixture screws are screwed right in and it's still lean.Air leak or pilot jets.Check the balance tube for splits or leaks.Even the thin Amal O-ring should still seal if the flange is flat.Triumph O-rings (0.100" thick) work better if you don't over-tighten.

It should run OK with the mixture screws 1-1/2 turns from bottomed.

Like loctitekid says,you should be putting a load on this engine;like within 20 seconds of 1st startup.Find the problem,then ride it.
 

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Discussion Starter #9
some progress

Checked floats..level ok..found what looked like water in one main jet..
blew it out and checked the other. Did not do pilot jets yet ( that's next).

Started it up ..and rode it around the neighborhood..with chokes on at first..as soon as it warmed up I could open the chokes(shut them off) and it ran good from about 1/2 throttle up...As soon as I slowed down, it would quit..so I guess pilot jet cleaning is next.

Can't get the smile off my face.
 

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You definitely need to rod out the pilot jet. The next to smallest guitar string is. 016" diameter and the way to go. (standard weight strings by the way, light weight is .002 smaller)

Mr. Pete's. advice is spot on. Pull the mixture scew and you can see the orifice about 1 1/2 inches in there. Use the wire to rod it out and then reinstall screw and fire it up!
 

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After a year...started my motor after a total rebuild by me!
Motor has a new Pazon ignition and a new set of AMALS.

Finally..after many kicks I got the motor to start..by lots of tickling
and full choke....in my garage which is around 60 degrees. Did the usual oil tank return check..that was good. HOWEVER...bike will not run unless on full choke. This is sitting still..reving the motor between 2500 and 3500....for a couple of minutes. I shut it off after that to avoid getting motor too hot. Restarting even after just a couple more minutes requires more tickling .

Obviously something is wrong with my new carbs. I did a float level check before I put carbs on..and made sure main jets were tight. I wouldn't think the dreaded " blocked " pilot jet syndrome would cause this?

Any hints?
Parlee,

All other things being equal, you'd not expect to be buggerising around with settings on new carby's, though it does pay to open them and check all the jet sizes and needles against the specs. The 1.5 turns on the air bleed screw will start and run 99% of standard engines.

if you have not done so yet, check all the components against the Triumph specs, and as Locktite Kid reminds us, an air leak is easy enough to over look.

The fitting of an EI to a rebuilt engine brings with it this dilemma.

you must free rev the engine to at least 3000 rpm to strobe it. The EI timing cannot be set any other way and running an EI fitted engine, with the timing anywhere but spot on, could end in tears.

I always use points for the initial start as points can be statically set pretty accurately, and good enough for an initial run under load. With points you can trailer the bike to a suitable location for bedding the rings, and run the engine to 5000 rpm under load, without fear of any engine damage.

In your situation, I'd have set the engine up with points and the old carbies, and after have bedded the rings, and with a few miles on the clock, started to add the new items one at a time.

So budding engine rebuilders everywhere, with the old Triumph engines anyway, do not throw away those points. They come in handy in this situation.

Free revving this engine, and/or puddling around suburban streets to check your carbies is going to leave you with a glazed bore and high oil consumption. Beware!!

RR
 

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Discussion Starter #12
i have 2 threads going now on the same subject..mostly out of frustration. I think timing is close to right based on how the motor runs at heavy throttle. Also..starts on 1-3 kicks..if I tickle the carbs and run the chokes. But it goes dead lean below 1/2 throttle( if i shut chokes off)...quits running completely...hence my suspicion that the pilot system is not working at all.So now I am trying rod out the pilot jets with a .017 wire..not sure how far the orifice goes..so I don't know if I am getting anything done?
 

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Use a .016 wire (or slightly smaller); believe it or not a .017 will likely not fit. You will feel the wire hit the orifice body and then you also feel it slip through the hole.

By the way, are these really new carbs?
 

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Additional thought - don't underestimate what maladjusted ignition timing can do. Please be sure that you have timing set properly.
 

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Discussion Starter #15
pls see my other post

Yes they are brand new carbs from Steadfast Cycle...in the AMAL box
etc....

Motor runs too strong for this to be a timing issue....actually feels
stronger than I expected
 

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Motor runs too strong for this to be a timing issue....actually feels
stronger than I expected
Engines will frequently run at their best just before they blow up!! RR
 

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Discussion Starter #17
o- rings and gaskets?

I just saw another post which made me ask.....I am running the AMAL
O- rings to seal carb to manifold. Do some guys run the o rings and paper gaskets ...at the same time?
 

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Discussion Starter #18
FIXED..unbelievably stupid mistake

Sit down while reading...you may collapse laughing..
Friend helping me today..asked what the little tubes were on the
intake manifolds......the ones where I forgot to put the little
rubber balance tube that connects them. Soon as I did that..things started acting normal and was able to obtain a 1100-1200 rpm idle.
After I strobe the timing..i will see if it will go lower.
 
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