Bonneville America Forums Forums Technical Forums Performance Mods Cuts Out after Performance Mods

I have a 2005 America with EPCO pipes (delivered in 3 days by Bella Corse), AI removal kit and Freak kit. I installed 160 Mains, 45 Pilots and 1 shim with stock needles. Pilot screw adjustment is at 3 (been as high as 4). There is very little popping and it accelerates great through all speeds and gears. At a steady (or slight acceleration) 60-65 MPG (around 3500 RPM) it cuts out. The worst is at that speed with slight acceleration. When cutting out, opening the throttle accelerates like a jack rabbit with no cutting out. It also seems to be by far the worst crossing or along the Indian River (East coast of Florida)…….go figure. I’ve also notice some cutting out in 4th at around 3500 RPM. I’m looking for advice from the veterans. BTW, I read some bad stuff from about 6 months ago on EPCO delivery. I ordered fron Bella Corse and the were delivered 3 days later

When it cuts out, does the motor just die? Or is it just losing power for a split second? you said many contrary things and we can't tell what the issue is unless you give a better description. Kind of like saying, "It's broke, how do I fix it?" Details! Give us details.
As far as what rpm it loses it in, try to determine what throttle position it is, such as 1/2, 3/4 or WOT. That is more helpful. Put some masking tape on the throttle and the bars amd make marks at 1/8, 1/4, 1/2, 3/4 and WOT. Use that as a reference for the requested details. If it is just in a particular RPM, let us know that too.
If it's a gas issue the throttle position is the key, if it's electrical the RPM is key. So both details is gooderer.

Hi Ed,
Sounds like you may need tapered needles. Triumph Thunderbird Sport needles is what I am using - never a problem like you describe. Another member recently posted some info about the Yamaha VStar1100 needles working very well. Wait for other responses before you go buy something. There are many others out there that are more knowlegable about carb adjustment than myself. The TBS or Yammer VStar needles wouldn't hurt. The V-Star has a dedicated website: NoPork that may be of some help. They do sell performance stuff.
Ride Safe,
Dennis

Sometimes it dies out for a second like running out of gas. In that case it dies, comes back, dies, comes back for as long as I maintain steady RPM/throttle position. At other times under the same conditions, more like a miss or sputter. It seems to be the worst at 1/4 throttle or a tad less at 60-65MPH, 3500RPM. Either no acceleration or very slight acceleration. Mainly in 5th but have felt it some in 4th. It clears up immediately if I dump on the trottle. Otherwise it runs great, although I don't think I've run it over 75MPH since the problem began (after the AI removal, EPCO pipes, Freak and re-jetting/shim jobs)

This is probably not it, BUT.... you may want to adjust you throttle cables. It almost sounds like one is not opening at the same instant as the other. Under heavy throttle, you wouldn't notice this. Just a though..

Check your gas tank vent tube.

Sounds to me like the dreaded "flat spot", but mine never cut out, only stumbled or hesitated once in awhile. The TBS needles cured this on my 03 TA.

Thanks for the responses. Who has TBS needles on-line? Haven't located any. On the vent hose, good thought. It believe it was pinched initially after I had the tank off last week. It died so bad then, I switched to reserve even though I knew there was plenty in the tank. I believe it is most likely a fuel/air mix problem at the particular conditions. It started happening immediately after installing the Feak, jets and shims. Can't be to quick to rule anything out. My wife's car air conditioner quit a day after an oil and filter change and tire rotation. She was sure they did it. I said no way. Wrong! They disturbed a wire harness changing the oil filter. A day later the fan wore through the wire controlling the AC compressor clutch. They figured it out after they replaced the compressor and it still didn't work.

Hi Ed,
Be sure to check your little hidden fuel filter at the "T" between carbs too, throttle cable while your tank is off.
I looked and looked online for the TBS needles. Finally ordered them from the nearest Triumph stealer. Took 6 days to get and paid way too much - $23.00, which included their order charge. For $38.00, I could have had them mailed to the house. If you can find out which VStar 1100 needles to use, I bet they'd be cheaper. You might try "ma's cycle" - you might have to call them.
Ride Safe,
Dennis

TBS needles are #N3RF
Triumph part #T1241024

I got mine from Palm Beach Triumph for $7 apiece

Click Here:

Palm Beach Triumph

Ed,

Mine had a similar problem. Turned out to be a piece of paper-towel/cotton that was obstructing the right carb's main jet.

Given that

Quote:

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When cutting out, opening the throttle accelerates like a jack rabbit with no cutting out

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it sounds like a fuel problem. Does your ride accelerate if you pull out the choke when it is cutting out?

Being as how your main needles are shimmed, you may, (by rolling on the throttle when it dies) be lifting the needle up enough to get the fuel you need. Why this hunch? Well rolling on the throttle won’t do much if a fuel line is clogged, but will do something if you are in essence making the fuel line larger. (Lifting the needle increase the main jet’s fuel transport)


PS Indian River? Anywhere near Merritt Island?

Thanks for the addition inputs. Ordered TBS needles through the closest Triumph dealer, House of Power, Palm Bay, Florida at $7.45 each.

Moe- I'm in Melbourne near BCC. I was up to the Port of Canaveral and back by way of Merrit Island last night.

Given the hunch, would that suggest 2 shims are better than one per needle?

It's taking 3 posts to get it all out! Pulling the choke when it is cutting out, results in a short spurt, but then goes back to pretty much the same bad behavior. I did get 4 shims but only put 2 in since that seemed the most common thing I saw in other postings (1 or none per needle). I may try adding the other 2 until I get the TBS needles.

Added a second shim under each needle this evening took it on a test run. I'd say it seemed to be about an 80% improvement. TBS needles due in early next week. I'll get back with the results after they go in. BTW, I discovered by sucking and blowing on the bottom of the gas cap and also the vent hose from the bottom of the tank, air goes only one way, outside to inside the tank through the cap and inside the tank to the outside through the vent hose.

I'm having similar problems with TORs, AI removed, Freak, 150 mains, stock pilots. Mine has never actually died and restarted, just "skips" a bit at constant speed. I'll be watching this post. Please share your remedy, when you find it.

Thump

Hey Ed,

Start the TBS needles without shims. Some have reported a too rich condition with one shim. I have an almost identical setup as in: TBS needles, AI removed, Freak, Epcos, 160 mains, but stayed with the stock 42s. Who recommended the 45s for you?

After you get the new needles in, balance your carbs before doing a serious test run....

btw, my bike runs darn near perfect in all RPM ranges and pulls like a freight train.

The 45s came with the EPCO pipes from BellaCorse.

Interesting. They did not with mine, although I have had them for awhile now. I guess time changes everything, eh?

Check your plugs. You may be running to rich because of a leaking Petcock. You describe the EXACT symptoms I had to a tee. A leaking Petcock will over ride your main jets and float settings if its leaking badly.

When I last posted, I was waiting for TBS needles ordered from the local Triumph dealer. I put the TBS needles in last weekend and finished tweaking the pilot screw adjustment this weekend. I could not asked for better results. Runs great running up through the gears and at all throttle poditions in between. There is virtually no popping and backfiring on deceleration. Current modifications and setup are: EPCO pipes, AI removal kit, Freak, 160 Mains, 45 Pilots and TBS needles with no shims. Pilot screw adjustments are at 2.5.

Thanks for all the help and suggestions!