Triumphrat

geolpilot · 01-16-2008

I took a ride today and had a surprise. After a straight stretch of road at about 60mph, I pulled over to the side of the road and stopped. The engine died and when I started it, it was popping and didn't run well at low rpm. I rode it home and it still seemed a bit funky at low rpm and idle and I needed to increase the idle adjustment. Well, I screwed in both pilot adjustments and neither seemed to make much difference at all. The setup was 2 pilots, 125 mains and 2.5 turns out. I have intact airbox with snorkel and Uni filter and TORs. After this attempt at adjusting the pilots, I left them at 2 turns out. Took it for a ride and it seemed fine.

Now, why don't the pilot screws make much, if any difference from screwed shut to 3 turns out? Should I take out the 42 pilot jets and put the 40s back in? Oh, just before this trip, I cleaned the UNI filter and oiled it with K&N oil. Could that be the problem? This bike has run perfectly prior to oiling the filter????? It may be o.k. again, it seemed to be on the test ride.

mikeinva · 01-16-2008

maybe to much oil in filter. the way it seamed to work out for me the bigger pilot i put in mine the more i had to turn the screw to get a change if that makes any since.with air bok still in you might not need but the 40 pilots .You kinda got to test and see what works best on your boke day in and day out.

Jimi_X · 01-16-2008

If it is running OK now, I would suggest taking it for a 20 min. ride, returning home with your Bonnie all warmed up. Before you shut down, check your idle. Is it stable? If so remember the rpm. Now remove the side cover and remove the air filter. Fire it back up. Check idle for rpm and stability. If it isn't stable, ( which is possible), gradually put your hand over the intake choking off the air. Does it improve or shut down at the first sign of restriction?

MES · 01-16-2008

Quote:

Originally Posted by geolpilot

I took a ride today and had a surprise. After a straight stretch of road at about 60mph, I pulled over to the side of the road and stopped. The engine died and when I started it, it was popping and didn't run well at low rpm. I rode it home and it still seemed a bit funky at low rpm and idle and I needed to increase the idle adjustment. Well, I screwed in both pilot adjustments and neither seemed to make much difference at all. The setup was 2 pilots, 125 mains and 2.5 turns out. I have intact airbox with snorkel and Uni filter and TORs. After this attempt at adjusting the pilots, I left them at 2 turns out. Took it for a ride and it seemed fine.

Now, why don't the pilot screws make much, if any difference from screwed shut to 3 turns out? Should I take out the 42 pilot jets and put the 40s back in? Oh, just before this trip, I cleaned the UNI filter and oiled it with K&N oil. Could that be the problem? This bike has run perfectly prior to oiling the filter????? It may be o.k. again, it seemed to be on the test ride.

Hold up there a second.
You would have to grossly over oil a filter to see thes type of symtoms.
did you make card adjustments directly before this happened?
If the answer is no, then first check for a vacuum leak.
check to see if the 4 nipples (or 2 hoses) are still there and not cracked.
(carbs and intakes)

This is a classic.
If your bike just starts stalling at idle or has a really rough idle, has no power or is popping really badly and you haven't done "anything" to it. Check the nipples.
The fact that the pilot screw did not affect the performance also points to this.
Give it a quick look see.

CAPTDON · 01-16-2008

Too many questions!! Is it your bike? When was it last ridden? How old is the gas?
If it was a dailly rider- I think the thread woulda started out as I took off today & ******** if it was ridden @ least weekly?

geolpilot · 01-16-2008

It was last ridden a couple of days ago. It has been ridden multiple times weekly and 2000 miles since early October. I checked the vacuum nipples immediately, but I did not pull them off. I also checked the carbs for security. I will ride it again soon, maybe tomorrow to check it better, but even when I first re-jetted it about a month ago, the idle mixture screws didn't seem to do anything, or at least not much.

RedBird · 01-16-2008

I don't think the pilot jet size has much if anything to do with your current problem; however, next time you are in the carb, I would suggest installing the 40 pilot jets...the 790 doesn't need 42's, IMHO. I have 42's in mine and the pilot screws are less than one turn out, and I have more mods than you. Size 40's would work just fine for my setup...I haven't taken the time to change them since getting it set up on the dyno.

I know you said you checked for vacuum leaks; however, it sure sounds like that is the culprit to me.

geolpilot · 01-17-2008

Well, I was just checking the carbs and I don't think I have any leaks. I pulled the filter out and I think I seriously over oiled it. I just washed it and will lightly oil and install it tomorrow. 42 pilots, presently 2 turns, 125 mains, 2 shims (maybe should be 1 shim???). Tors and Uni filter, airbox and snorkel original.

Nzbiker · 01-17-2008

A good way to check for vacum leaks is ti spray around the inlet rubbers and vacum bungs with engine start (ether) or wd 40 if the idle increases its got a leak

Cheers