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Discussion Starter · #1 ·
So i just picked up a trophy 1200, and I’ve recently had some trouble starting it up. It had been sitting for a few months with stabil. The last owner got it running fairly quickly and it was riding etc while i bought it. we were able to turn it off and on again a few times while checking it out no problem. Fast forward to getting it home and i let it sit for a few days and again it’s hard to start. occasionally backfires and sputters etc.
after replacing the gas I had it running for a little bit twice, but i always had something else to do.

last time i got it running was tuesday,
but i messed up the choke / idle adjuster and killed it, i got frustrated and left it at that.

I set the battery to trickle charge overnight and tried to start it today without a jump - no dice, just one loud backfire. for obvious reasons i’m now a bit afraid of starting the bike and doing damage to it, i don’t want to flood the engine or ruin the sparkplugs.
regardless, should I always need a jump to start the bike if the battery is charged and good (according to advance auto)? any tips for the idle adjuster and choke? how do i know if i flooded the engine? could something else be the cause of all this trouble? This is my first carb’d bike so any help would be great.
thanks!
 

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Hi Microvolt, Welcome to the world of Triumph Trophy. First off. The Trophy is top heavy, be careful pushing the bike in the garage or driveway. If you lean the bike too far down it goes. Many owners have dropped their bikes in the garage and say goodbye to the turn signal. The Trophy weight goes away after 30 mph. The Trophy is a freeway flyer and loves to cruise at 70 or above. Next. The engine is almost bullet proof except for the sprag clutch. The sprag clutch (starter clutch) is the only weak spot on the engine. You can protect the sprag clutch by having a good fully charged battery. The Trophy is like a woman, if you ignore the bike, it won't start up. Letting the bike just sit in the garage for two weeks or more is not good.
Now to your question. The Mikuni carb's idle jet is very small and with this crappy part alcohol gas we have to use, the jet gets clogged up when the bike just sits for weeks. The cold engine will only start with full choke and no throttle even when everything is all good. So if it didn't start the carbs won't be flooded. That only happens when the float bowl assembly doesn't turn off the gas.
How comfortable are you at wrenching and working on bikes? Not many Triumph mechanic are familiar with carbs and they will charge a lot of money. Sorry to say but you will be needing to do some carb work in the near future. But it is not that hard. Many guys on this forum can help and talk you thru it. Here is some good sites to know.
Hope all this helps,
Greg
 

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1996 Trident 900 & 1999 Trophy 1200
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I purchased a '99 Trophy 1200 in Sept., The bike ran,,,"OK, but was clearly in need of some combustion attention. It didn't have the power or acceleration I expected, and the bike would not start on full choke- only half choke, which is a tell-tale sign of a carb problem., I'm a handy guy, but not ready to rebuild 4 carbs and sync them.

So, I brought the bike to my motorcycle guy (I also own a 96 Trident). He rebuilt the carbs, replaced plugs with iridium plugs, and synced. The bike runs great! accellerates, runs smooth, and, typical of '90's triples (and 4's), starts cold with full choke, no throttle.

My rec is to tear down the carbs and replace plugs and wires, possibly coils.
Wheel Tire Land vehicle Fuel tank Vehicle
 

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Discussion Starter · #4 ·
Hi Microvolt, Welcome to the world of Triumph Trophy. First off. The Trophy is top heavy, be careful pushing the bike in the garage or driveway. If you lean the bike too far down it goes. Many owners have dropped their bikes in the garage and say goodbye to the turn signal. The Trophy weight goes away after 30 mph. The Trophy is a freeway flyer and loves to cruise at 70 or above. Next. The engine is almost bullet proof except for the sprag clutch. The sprag clutch (starter clutch) is the only weak spot on the engine. You can protect the sprag clutch by having a good fully charged battery. The Trophy is like a woman, if you ignore the bike, it won't start up. Letting the bike just sit in the garage for two weeks or more is not good.
Now to your question. The Mikuni carb's idle jet is very small and with this crappy part alcohol gas we have to use, the jet gets clogged up when the bike just sits for weeks. The cold engine will only start with full choke and no throttle even when everything is all good. So if it didn't start the carbs won't be flooded. That only happens when the float bowl assembly doesn't turn off the gas.
How comfortable are you at wrenching and working on bikes? Not many Triumph mechanic are familiar with carbs and they will charge a lot of money. Sorry to say but you will be needing to do some carb work in the near future. But it is not that hard. Many guys on this forum can help and talk you thru it. Here is some good sites to know.
Hope all this helps,
Greg

So, for extra info the bike recently underwent a full carb rebuild, which i have receipts for. And for future reference, how do I know if the Sprag clutch is going out?
and unfortunately because of where i live (we get some heavy, heavy snow) we usually end up having to have our bikes sit for a while. The tank, as. if right now has e0 ethanol free fuel. I might call the shop who did the carb rebuild and see what they have to say.
Thanks!
 

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Hi Microvolt, Filling the tank with ethanol free fuel is the right thing to do for winter storage. I'm doing the same for my two Trophys and Sprint. I'm in the White Mts. in northern Arizona at 7,000 ft. Our streets are clear but I've got 30 ft. of gravely mud between my garage and the asphalt. It's a good day for a ride but I don't want to drop the bike in the mud. I gave my long time ride (900 Trophy) to a long time friend. It ran perfectly. After a year he bought a Tiger so the Trophy did too much sitting. He couldn't get the Trophy to start. He thought it was an electrical issue, I thought it was the idle jets. I came back to Calif. for a visit. I confirmed the spark was good to reassure him. I took off the carbs. Yep, there was junk in two idle jets. I cleaned out the jets, and put it all back together. It started right up. He was amazed how easily it started. The point of this story is that correctly rebuilt carbs can have problems when the bike just sits. The carbs dry out and a residue is left behind in the very small idle jets. The lengthwise hole in the idle jet is only 0.011 in. the equivalent of a #79 drill bit. That about 4 time bigger than a hair. There is another small jet in the float assembly equivalent to a #74 drill bit. but this jet sits near the bottom of the float bowl and it usually doesn't get dried out.
On to the sprag. It is buried in the engine and the cases have to be split apart to get to it. Lots of work. It is an amazing one way clutch. It spins freely in one direction and immediately locks up when turned the other way. There is a long spring going around the circumference inside the sprag. It is the spring that makes it work. When the sprag goes bad
it sounds like a little guy is inside the engine and hits the engine inside really hard with a big hammer. WHAM!
So what is happening when the Big Bang Wham hits. One of two thoughts.
1. The engine is turning over so slowly with the bad battery and the advanced ignition fires the gas charge and it makes the engine turn backwards and the sprag clutch catches the backwards motion and stops the engine from turning that way. Or
2. So you press on the starter button and the starter spins the sprag in the locked up direction and that turns the engine over. When the sprag goes bad it will not lockup immediately, so it spins for a second or two and then locks up.
Somebody tell me which one is correct.
The moral of the story is have a good battery and keep it fully charged.
Greg
 

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1996 Trident 900 & 1999 Trophy 1200
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Hmm. Carbs reworked recently, battery good. Sounds like a possible ground in the starting circuit. Definitely bring it back to the shop that did the carb rebuild to get their input.
Where are you riding?
 

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Hi CT, Bad coils and wires tend to show up with wide open throttle (WOT), not low throttle settings.
Replacing the spark plug wires and coils can get expensive if you go with factory parts. Sprint Manufacturing UK has the parts and better pricing with fast delivery even though they are in the UK. As for poor acceleration and power, check that the vacuum slide diaphragm is in good condition and not missing the little o-ring under the cap. Or take off the air filter and lift each slide with your finger. They should not slam down and go down evenly.
Greg
 
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