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I've had my '93 Trident about 6 months now, and the carburation has always been bad at the bottom end. Judging by the butchered airbox etc, everyone of the previous umpteen owners has had the same trouble. The airbox is sawn verically in half amidships, most of its screws are missing, and the snouts have been trimmed off the intake silencers to make access easier. The outer rubbers on the Mikunis were hard as rock during the British winter so had been badly fitted many times before, probably shrouding the crescent shaped slots above the chokes.
There was areally bad flat spot that would sometimes dump me on my ear pulling away from cold. Not nice, but she ran a lot sweeter when hot.

An attempt to balance the carbs with dial type gauges proved fruitless as the readings were all over the place. The carbs had been cleaned out so many times before the gaskets were compressed and the jets had seen plenty of butchery, but were still useable, Pilot screws were 5+ turns out.
In desperation I borrowed a set of digital vacuum gauges. The results were immediately obvious as the left hand cylinder seemed to have a life of its own when it came to vacuum and sync. The bike always seems to run OK when hot, or when the air temperature was up, and although there were classic signs of weakness it couldn't all be down to jets.:mad:
The fault was actually caused by the raditor hose that comes from the top left of the rad, down between the block and the L/H and central carb. When cold, this hose is stiff and contacts the centre tab of the throttle linkage for the l/h carb. The result is that the springs on the linkage are forced to compress either way the throttle moves, i.e. late opening, then hanging up followed by late closing of the l/h carb butterfly only. As the engine warms the hose softens and the springs re-assert themselves and it goes back to how it should have worked all along, except the springs were so weak after 15 years of this, that the l/h carb sync was able to wander about. There are fret marks on the hose, but nothing serious enough to cause a leak.

I have now re-routed the hose outside the l/h carb, and perked up the springs on the linkage, so now we are balanced as we should be (well the bike is), and what a transformation!

The digital gauges also allow you to diagnose possible valve leaks, and luckily none showed up, so now I can finally enjoy the performance. Better yet the sun is shining! :)
 

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Thank you Hamwic, having just replacve the sprag clutch in my bike and the hose you mentioned, the bike seemed to be running a little different as if the fuel enrichment (choke) was stuck, also it was trying to stall when taking off. Having not had a problem before, i pulled the tank and plugs and found no1 was a little richer than the others, could not figure out why. Now i will have to go and investigate this tomorrow.
 
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