News:

The simplest way to help GStwin is to use this Amazon link to shop

Main Menu

Bike doesnt need choke to run - is this a problem?

Started by BikerBoy, June 17, 2019, 12:24:39 AM

Previous topic - Next topic

BikerBoy

So my bike got painted and washed and had new jets put in the carb 20 60 137.5 and new k&n air filter for stock airbox. Starts right up at 1100 rpms, sounds great, carbs just got synced. But my bike USED to need a choke to start up, even in these hot texas summers of 100+ degrees. Since changing the jets and air filter something happened. But, is my problem really a problem? Because if it just increases speed and performance, and makes the choke completely unnecessary, I'm all for it! Thanks  :woohoo:

qcbaker

If your bike doesn't need choke to start, its almost definitely running super rich. Over time, unburnt fuel and carbon will deposit on the spark plugs and the valves, which will eventually cause problems.

IdaSuzi

I also agree it is probably running rich. Look out for the gas smell in the exhaust, but also take the spark plugs out for a look after you have put some miles on it. If they are black and sooty then you know its too rich. I actually has slightly larger jets than you have but with a slip-on and drop in filter. Even with the weather being around 80-90 F here I still have to let it run on full choke for 30 seconds or so then half choke for another minute or so. If its only been sitting for an hour or so after a long ride I can start it on partial choke. It warms up much faster than stock but still needs the choke on cold starts, so in my anecdotal experience you probably should take a look to see if it is too rich.
1998 RM125
1995 RM250
1999 Yamaha Banshee (Kind of a bike???)
1993 DR350
2008 GS500F naked conversion, Kat 600 shock, Yoshi Slip On, Progressive Springs, 20/62.5/140 rejet, Fenderectomy, LED Front and Rear Signals

BikerBoy

Quote from: IdaSuzi on June 17, 2019, 03:38:16 PM
I also agree it is probably running rich. Look out for the gas smell in the exhaust, but also take the spark plugs out for a look after you have put some miles on it. If they are black and sooty then you know its too rich. I actually has slightly larger jets than you have but with a slip-on and drop in filter. Even with the weather being around 80-90 F here I still have to let it run on full choke for 30 seconds or so then half choke for another minute or so. If its only been sitting for an hour or so after a long ride I can start it on partial choke. It warms up much faster than stock but still needs the choke on cold starts, so in my anecdotal experience you probably should take a look to see if it is too rich.
I see. So do you think me putting a new/used exhaust (delkevic ss70) would lean it out a bit? Thanks

IdaSuzi

An exhaust with less back pressure would certainly lean it out some and couldn't hurt since you have already went up in jet size. However, I still wouldn't rule out needing to adjust the air fuel mixture. But definitely go with a pipe at some point! I love my Yoshi pipe
1998 RM125
1995 RM250
1999 Yamaha Banshee (Kind of a bike???)
1993 DR350
2008 GS500F naked conversion, Kat 600 shock, Yoshi Slip On, Progressive Springs, 20/62.5/140 rejet, Fenderectomy, LED Front and Rear Signals

SMF spam blocked by CleanTalk