Boxerworks.com

all,

thought some of you could chime in and share your thoughts. i've owned several airheads and just sold my 1983 R100RT after purchasing my new to me 1995 R100RT w/19K miles - just fully serviced at dealer in california where i purchased it. the bike arrived to my home in seattle today and was unloaded at 10am.

i tried starting it and found it difficult - temperature about 65 degrees today and bike was last run about 2 weeks ago at dealership.

when starting, it requires the choke be on fully for a long period of time - and choke at full opened position, it needs to idle for at least 2 minutes before i can close the choke to the 1/2 way position - after another minute or 2 i can turn off the choke completely. *i really can't turn choke off and use the throttle until it has idled with the choke for this amount of time or bike will cut out and turn off. *after idling for a while this morning i turned it off and restarted about 2 hrs later - same scenario - needs choke for several minutes.

it's idling at about 800rpms and very quiet/consistent at that point after about 4 minutes.

*with my other R100's i would use the choke for about a minute and then pretty much be able to turn the choke completely off and the bike would respond to the throttle without cutting out.

does this sound strange at all??

thx in advance.

Idling too low. Bump it up to around 1000-1100 rpm.

Are the choke levers fully engaging on the carbs? They might need adjusting to get full on and full off at the extremes of the handlebar lever movement.

Kurt in S.A.

I am thinking that your problem may be in the carburetors, like the idle passages being blocked with old gas varnish residue.
This is a 21 year old bike, which according to the mileage must have sat a long time with gas in the bowls. The extensive use of the choke would indicate that it is not getting enough gas under normal conditions, even when it had been only shut off for only a couple of hours. Pulling the carbs and a good cleaning is in order IMO.

Fresh fuel might help.

Fuel is not a homogeneous mixture that evaporates evenly when exposed to air as it is in a vented carb bowl. It's made up of a number of different components and after only a few weeks the more volatile fractions evaporate off. That won't help with starting and cold running.

I'm guessing that the idle mixture is on the lean side. If, after riding the bike for 25-30 miles to get to full operating temperature, the idle speed goes up to 1200-1500 rpm that could be the problem. Readjust the idle with the engine at op temp and see it starting improves.

really appreciate everyone's input!

so heres the latest: i finally got time to take the bike out for a drive today (i turned idle adjustment screws up yesterday so the bike is idling at 1100rpms) and here is the procedure i used - 65 degrees today and sunny:

to start: cranks right over with full choke for 4 minutes with some throttle, then i am able to turn down choke to the off position *if i attempt to turn the choke off during the 4 minute time period the engine will cut out even if i attempt to use throttle.

after the 4 minute warm up period the bike idles perfectly - after a 45 minute ride around town the bike is idling perfect and all runs smooth. took it out again for an hour and just got home - bike runs really smooth and love the monoshock suspension - idle steady at 1100rpms

so basically it is just the amount of time it takes to turn the choke off. with my other RT's 81 R!00 and '83 R100, i use the choke for 30 seconds max and i can turn it off and use throttle.

since it has been recommended the carbs be gone thru, do you guys suggest i send them to BING and have them do the work? any idea of cost for BING to do them vs indy shop??

thx in advance!

I'd probably start with half a bottle of Chevron Techron (or BMW's own fuel system cleaner, reported to be a concentrated version of Techron) into two successive full tanks of fresh gas, to see if that cleans out any gunk in the carb passages. A pretty cheap experiment---$7 at your local auto parts store ($14-ish for the BMW version at your local BMW auto or motorcycle dealer).

I have had a couple of bikes that I bought after setting for a long time and I have found that using Seafoam after getting it started helped. Then you go in and start the cleaning and tuning