Triumphrat

jedrake73

So nothing major has gone wrong with the bike yet, but I had 2 days in a row with different odd symptoms that I would like to get opinions on.

For reference, it has been over 90 degrees here the past week and this is my first time having this bike in temps this warm.

First symptom: Yesterday I decided to take the long way home and went for a blast down my favorite mountain rode when the bike ran out of gas... 10 miles after switching to reserve. Now, I've never ridden the bike more than 10 miles on reserve before but by my calculations I should have had another 20 -30 miles before I ran out. I couldn't see any gas when I looking in the tank so just thought it was empty, but it seemed odd. Now I'm wondering if it may have been a vapor lock condition where the gas in the line or in the float bowls was boiling and when I got down under a gallon there was not enough pressure from the weight of the gas to feed the carbs. Of course I did not wait for it to cool down and try again, I had my wife bring me some gas, filled it up and off I went.

Second symptom: Today after my 1 hour commute home in stop and go traffic I was sitting at the stop light on my offramp for a few minutes and heard a sort of loud pop from under me followed by a distrinct change in my idle speed - dropped about 200 rpm. Not like a backfire pop, it sounded like one my the vaccuum caps on my carbs or intake blew off. But I looked down and they were all fine. I have mine secured with small hose clamps and they were all intact and hadn't burst. So I rode off, no problem. I got up to the next stop light and after idling for a few seconds at normal idle speed, pop! and drop in idle speed. Odd. I got home and let the bike idle and it did not do it again but the idle stayed low. I have never heard anything like this before.

My engine oil temp gauge readings haven't changed much though. I usually am around 210 and when sitting will get up to 240. Which incidently is about 20 degrees warmer than my America used to run but I attribute it to my pipes and airbox mod (not sure if this is correct).

So right now, no ridability issues I just want to see if any of you all think these may be signs of a bigger issue or something to do with the heat.

peterbear

jed you dont mention at what stage you have the tuning up to .IE stock ,after market pipes ,different air cleaner. i had a similar problem with my bonne when at the lights it would pop back thru the carbs and the idle dropped. i put it down to ( my bike as i havent got to put it correct jetting yet with aftermarket pipes and unifilter.) wrong mixture until i get it right.
peter.

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Peter

jedrake73

Yeah, I'm not exactly sure of the tune on the bike. I got it about 2 months ago and it had staintune pipes and airbox snorkel removed. I pulled the AI. It runs much stronger than stock bonnies I've ridden and only pops ever so slightly when coming off the throttle - about a quarter of what you would get stock. Haven't checked the jets or needles yet - figure'd I'd leave well enough alone until I have to.

webonnielad

I didn't believe it could have such a huge effect as it does either.
But check your fuel cap vent valve. If thats jammed it can replicate a whole load of psuedo symptoms.
I've been chasing my tail for weeks.

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790cc 2003 T100 Bonneville. 18T Front Sprocket, AI Removed, 125 Mains, 40 Pilots, Thruxton Needles, 1 Shim,3mm Air Hole, Mixture screws 3 1/4 turns out left carb, 3 turns out right carb, Unifilter, NH Belmouth, NH Classic Togas with no mutes inserted, Stock Ignitor Unit. Hagon 320mm rear shocks & progressive fork springs. Last measured. 61.60 hp, , Max torque 48.40 in 5th gear at the rear wheel at 7200 rpm, 105 mph in 5th at 6500 rpm.