Hit A Bump - Now Needs Choke?!!!

I don't think I've been this close to pushing this thing into the lake. After finally getting it running well - the best it ever has as long as I've owned it - on my way home from work last night I hit a largish bump (our city streets are a disgrace right now) and I swear I felt something "give" on the bike somewhere. Hard to describe - and it could have been my imagination - but I swear I felt something sorta jar loose. Anyways - immediately the bike starts running terribly. Really sluggish and threatening to stall. I manage to limp it home only by cranking the choke. It was running really rough and backfiring once in a while. I started it this morning and same thing. Running terribly (but running) and only with full choke.

I know I should give it a good once over, but I have zero time these days to tinker (2 month old baby at home) and am hoping that maybe someone can point me in the right direction once I get a few minutes to look at it. What I have quickly checked:

The air filter is in place (thought it may have jumped out of position).
The coils appear to all be connected.
All visible carb connections seem to be in place.
The battery and TCI connections seem to be in place.

Once I have time I can try my colourtune plug to see if something is not firing, but in the meantime anyone have any ideas?!

Jimmytime

 

Where in toronto are you? I'm in Brampton,if you need some help.You should check your fuse box if its the old style.

 

It's a new fuse box - forgot to mention that I checked that too! Well, I at least checked to make sure that all the connectors were on correctly.

I'm in the west end - Parkdale. At this point I wouldn't even try to ride it to Brampton - it was running so bad last night!

 

Could be anything, I'd start with the easy stuff. Ignition coils(check for good spark), vacuum hoses and petcock tubing. If it has fuel and spark it should run. Sounds like a elecrtical connection may have beeen knocked loose, check them all.

 

i think either that or one of your carbs pulled from an intake boot and now has a leak...make sure your carbs are nicely attached to your air intake

 

Thanks for the suggestions!

Yeah - I immediately suspected an air leak or something similar, due to the fact that having the choke on kept it running. Though I guess it really could be anything. I'll try to look again when I get home.

 

Hey maybe check your vacuum line to the petcock

 

+1 for dbikers and blackmax.
It sounds like a manifold has come loose-check for a snapped
bolt .
OR......the vac hose is shot or pulled loose.My bike suddenly
started to have fuel issues out of no where. As I started to pull
the tank to check the petcock I saw the cracks in the vac line.
Had some on hand and was on my way ten minuts later.

 

It's been a while since I posted this thread - but it's taken me this long to have anything update. Due to my lack of free time, I ended up taking it to a local shop to see if they could quickly figure it out. They fiddled a bit, couldn't see anything external, and basically figured it must be the carbs. Knowing I didn't want to spend a lot of money they didn't actually go into them, and didn't charge me anything when I picked it back up (I couldn't justify paying someone else to strip the carbs down - I could probably do it in my sleep!).

I've since had the carbs off twice, and just finished giving them a good cleaning. Put them back on and it's no better. Keeping in mind that I completely tore them down in the Spring, replacing throttle-shaft seals, boiling them in lemon-juice, the whole thing. They were still super clean, but I cleaned them anyways! But like I said, still no good.

I know they are being supplied with gas. Opening the drain plugs shows me that they are all being fed. I know it has spark. I used a Colourtune to prove that. I know that it has compression - checked all four cylinders. I've tested for air leaks and can't seem to find anything. I've checked the manifolds and they all seem fine. Vacuum hose seems fine. Running it with the choke on "fixes" the problem in the sense that I can actually ride it - but it certainly doesn't run great and starts running worse once it's heated up. If I kill the choke while driving along it immediately starts missing and back firing, and if I kill the choke while idling the engine dies right away. I guess it's either an air-leak or a plugged fuel passageway in the carb that gets bypassed once the choke is engaged. The one thing that I noticed when using the Colourtune is that number 3 and maybe also 4 didn't seem to be firing consistently if the choke was off. Once the choke is engaged they would start firing consistently. Number 3 seemed worse than number 4.

I would welcome any suggestions anyone might have, but I'm really thinking about packing it in. As hard it is, I am pretty much done with the Seca. After 8 years I've never had a single full riding season out of it and it seems like whenever I fix one problem 3 more appear. I used to enjoy tinkering and fixing things, but now that I have a baby my free time is limited and I would rather spend it riding! If I don't get it working easily and soon I'll probably be selling everything (I have a lot of spare parts - including an extra Seca tank and 3 banks of carbs!) and maybe pick up a KLR or something fuel-injected in the late fall!

Unless someone here can suggest a magic-bullet fix and Save The Seca!

 

it's running lean, thus the choke, you already checked for vacuum leaks
put it on the center stand and check the float levels with a clear tube
then put the tube into a clean jar and the petcok to prime on each carb to see of some junk can be rinsed out
if a lot of junk comes out the pilot jet may be plugged
a cheap and dirty way to MAYBE fix it is take off the top of the carb and shoot carb cleaner down the pilot air jet( the one with the bigger hole) WATCH FOR BLOW BACK
leave the drain open to see if any more crap comes out

 

When I had them apart I checked and cleaned all the jets, so I don't think they could be plugged. I haven't checked the float levels - assuming one was off, would applying the choke somehow fix that? Does the fuel-enrichment circuit draw from the very bottom of the bowl?

I'm experiencing deja vu! I think I asked that same question years ago!

 

when you hit that big bump you might have bent a float but i really doubt it but what might have happened is it sloshed up some crud that was laying in the bottom of the bowl and it got stuck in the pilot jet
the enrichment circuit makes everything real rich, changes everything
yes the choke circuit draws from the bottom of the float bowl

 

Thanks for this! My hope is renewed (for now!). When I had them apart I checked all the jets (clear) and even sprayed cleaner into the pilot jet post. Everything seemed clear to me. However if the float level was off, then maybe fuel isn't reaching the jets and by turning on the choke it's being fed from the bottom. I'll try my best to get back at it soon - maybe by snowfall!

Thanks again!

 

Exhaust leak?