The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: aarm on October 18, 2012, 01:26:08 AM
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Hi All,
Now that the weather is colder, I'm having dickens of a time getting the R65 started. Once it's warm, it fires right up, but with the choke all the way on I'll get an initial sputter then it'll die. If I lay on the starter it'll fire up eventually, but I'm a little at a loss.
Let me preface this by saying, I had a shop rebuild the carbs back in April. They mentioned that they thought the choke may be sticking a little even after the rebuild and I may want to address that. Along those lines, if I leave the choke on after it's started, it can die as quickly as well. This was the case in warmer weather as well. Is this a flooding issue or more likely a lack of fuel issue?
Any thoughts?
Aaron
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Drop the float bowls, Aaron, and check the small fuel reservoir for the enrichener circuit. Identify the reservoir by observing the long brass pick-up tube that resides within.
At the bottom of the well, there is a tiny "jet" that allows fuel from the main float bowl to enter the enrichener reservoir. if the jet is clogged, it's the devil getting a cold engine to light off as no fuel can reach the circuit. Could be on just one carb bowl or both.
Strip a single strand of thin copper wire out of some scrap wire. Use the soft copper to poke through and open up the fual residue clogged jet.
Confirm the return springs for the enrichener lever are, well, doing their return job.
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Not sure what year your bike is. I believe choke operation got more progressive on later models. On my 79 the choke is not very sophisticated in operation. Above 12-15 deg C I need no choke at all. In colder weather I need to use full choke to start the engine but then have to take it back to half choke or even off almost instantly. No way will the engine run for more than a couple of secs on full choke except perhaps at - 15 deg C.
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mine is the same, when its warm starts so easy, but then cold, it starts for like 1 sec then dies, but if i hold down the starter then it wants to start, after about 10 starts and fine tuning the lever on the choke it finally will stay started, i figure its once the carbs warm up a bit or the chamber itself?
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Mine normally starts instantly hot or cold. It just won't run on full choke and the choke operation is not progressive it seems to be either full on or almost off. I believe the reason might be that the earlier carbs have fewer fuel holes in choke disc. If I had a later disc to copy I might be tempted to drill some extra ones.
If I get it wrong which is rare (but it did happen this morning after the bike had not been used for 10 days) then it can be a bit of a of pig to start.
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At the bottom of the well, there is a tiny "jet" that allows fuel from the main float bowl to enter the enrichener reservoir. if the jet is clogged, it's the devil getting a cold engine to light off as no fuel can reach the circuit. Could be on just one carb bowl or both.
Monte, do you have a photo.. or did this never happen?
I've been having a bit of trouble getting the bike to light off, even over the summer when it was Texas (tm) hot, and I suspect it's that or I need a carb synch. Or both.
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At the bottom of the well, there is a tiny "jet" that allows fuel from the main float bowl to enter the enrichener reservoir. if the jet is clogged, it's the devil getting a cold engine to light off as no fuel can reach the circuit. Could be on just one carb bowl or both.
Monte, do you have a photo.. or did this never happen?
I've been having a bit of trouble getting the bike to light off, even over the summer when it was Texas (tm) hot, and I suspect it's that or I need a carb synch. Or both.
Gots photo. Lemme find it and post.
Matt, You going to be in downtown Luckenbach on Saturday? I'll be wearing my black "LuftKoph" T-shirt. The cat with a Shiner in has hand.
Found it!
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fi196.photobucket.com%2Falbums%2Faa1%2Fmontmil%2FBMW%2520R65%2Fbowlvent.jpg&hash=65c063b41f1a9c7ccb68da1b4a6641bd6d3e8e37)
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After you go through the carbs and you still have the problem, check the ignition coil .
I had an OEM replacement red and black coil go bad on me, the cold hard starting problem started at 55 F. and got progressively worse with the temps getting colder .
The primary circuit of the coil had .7 ohms, should be 1.5 ohms .
Another possibility, is a dry starter, one where the lubricant has long since dried out .
This results in more battery power going to operate the starter and not enough to get the ignition to fire a good 'healthy' spark, especially the bikes with electronic ignition, this system doesn't work well with battery voltages below the 10 VDC range .
With cooler, or colder overnight lows, alcohol fuel is harder to get vaporized .
This possibly combined with an older battery that is not as good as it used to be .
I don't know if you have too much of a corrosion problem in Portland, but checking the charging /starting cables and wiring for corrosion, etc....., these bikes are approaching 30 ish years old in most cases .
There are a few possibilities, or a combination of factors causing the problem .
I'd get the carbs looked at first and if you still have a problem, then go into the electrical system .
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Thanks for all the responses. I think that the the reservoir "jet" is an easy first check. Monte, thanks for the pictures that makes it a no brainer.
If not that, battery and coil tests are my next course of action. Seems like a pretty common thing on these bikes as I remember reading about the clocked float boat jet in the past.
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To clarify the symptoms you will get if the jet in Monte's picture is blocked. If the jet is so completely blocked that no fuel can ge into the pipe at all (easily checked by dropping the bowl and looking in the pipe) then choke operation will provide no enrichment at all.
If the jet is partially blocked typically the engine will start on choke and run for several seconds until the "pipe" is empty. Then because the pipe can't refill from the float chamber or can't refill quick enough any additional enrichment will cease and the engine may stall. To be clear that jet being partially blocked does not prevent the choke working initially it just doesn't last very long.
The function of the jet is to restrict fuel flow to the choke once the pipe has initially been emptied. This is supposed to have the effect of reducing the initial gross starting level of enrichment after a few seconds of running.
Therefore if the engine runs rough from the instant it fires up I doubt this jet is your problem.
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When I bought my R 90 it was early summer. It ran fine and did all the servicing that you should do for a new to you bike. Come cooler weather it was hard to start just like yours is doing. Found the fuel bowl stopped up. Unstopped the oriffice and everything has been fine since.
Don
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Hi Aaron!
You've gotten some good advice.
I recently worked on an engine with cold starting, and after going through everything else, took a look at the chokes themselves. Turned out the last guy in there didn't know they were 'handed' and got them swapped side to side - left in the right side and vice versa.
So that's always a possibility to check.
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Barry thanks for laying out the troubleshooting logic. More and more it just seems like the choke jet may just be partially blocked. But I'll know when I get a chance to look.
You all are such a great resource thanks for the help!
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My bike has always been pretty particular about the choke. In warm weather (70F) and above, it rarely needs any choke. But below that, it does need some to get started but once started it will not run with the choke on.
What works for me is the following: crack open the throttle just a little, hit the start button, and while the starter is turn gradually apply the choke until the engine is running. Then bring up the revs with the throttle, and take off the choke. Keep it running at about 1500 rpm by adjusting the throttle as necessary until the engine is warm. Once warm, it idles fine.
PS, the comments about the starter and coil are good comments. I ended up replacing both a year ago, and it does start much easier.
YMMV
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Well, today I used the wire technique on both copper stems and the jet vent on the bottom of the bowl. I also turned the idle screws up a little.
Started great after even though I didn't see any goo come out, but it's much warmer today at 60 F. Not sure if the choke is the issue, but will see on my next cold morning or evening start. Replacing the coil could be next on my list, but I'll need a multimeter first.
Any recommendations for a good cheap one? Harbor freight has a bunch but not sure about the 5 dollar one.
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Another thing you might want to try is to push the "choke" past full on and hold it there while cranking. This may be an idiosyncrasy of my bike alone but it does get it started on those cold, dark mornings when I just want to get to work.
[ch8194]
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Thanks David. Any chance you bought your bike from a guy in SE that was selling to buy a family sailboat? Stored in a side yard in a small hand built shed?
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Yes Aaron that is the bike I bought. It has been a great one for me. Was that your bike?
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<snip>Replacing the coil could be next on my list, but I'll need a multimeter first.
Any recommendations for a good cheap one? Harbor freight has a bunch but not sure about the 5 dollar one.
I am not sure if you have the "points" ignition, or the electronic ignition. For those of us with the electonic (1981 and newer), almost everyone here has gone with the Dyna Brown coil. If you have a 1979-80, the Dyna Green should be the one.
http://www.motoelekt.com/ignition.htm
Not necessarily cheap, but reasonably priced, and very solid and reliable. It will put an end to any coil issues.
k_enn
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David - I test rode it and thought about buying it. It had awesome maintenance records. Glad it stayed in portland.
K_enn - it's an 83, so the Dyna Brown would be the path. Thanks for the recommendation
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Well tonight it's dropped into the 40's. I tried starting and the same sputtering and no start. I'll be checking the coil this week. Battery was holding fine even after running the starter for a good 30 seconds. Probably not the battery.
Checked pricing on starters. Ouch. 300+ from Bob's. about 200 from motobins. Any other resources that people can recommend.
The coil was under a hundred, so that would be a better choice to start with.
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you should try to post a video if you can, once i get my mini tripod ill post one up of mine
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Before throwing money at it and to try and confirm if your problem is fuel or spark have you tried pulling the plugs after the first starting attempt. If they are dry it's probably lack of fuel if they are wet it's likely a poor spark.
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$200 is about right for a starter. This is what I got:
http://www.euromotoelectrics.com/Starter-BMW-R-Airhead-9-Tooth-BMW-VAL1-p/bmw-val1.htm
Just be sure if you need the 8-tooth or 9-tooth for your bike.
If you have the Bosch starter, you might be able to have it rebuilt for less.
k_enn
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...Checked pricing on starters. Ouch. 300+ from Bob's. about 200 from motobins. Any other resources that people can recommend...
Don't throw money at a starter right now. Continue checking the simple things until all are either eliminated as problems or fixed.
When I return home on Monday, I'll post a link for starter rebuild kits... unless someone else reads this and does so. But doubt it's the starter.
Right now, I'm in Luckenbach, wrapping up another great Harvest Classic. So many great vintage bikes of all flavors.
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If you decide to do something with the starter, it doesn't need to be replaced, just cleaned and lubricated .
If you don't feel comfortable doing the job yourself, a local shop that specializes in alternator, generator and starters, should be able to do the job for a nominal charge .
You need to do some troubleshooting before replacing parts, the 'shotgun' method of trouble shooting can get costly and not fix the problem .
Here's a link to do a rebuild on a Bosch starter .
http://www.thisoldtractor.com/gtbender/print/moto_guzzi_loopframe_electrical_starter_and_solenoid_repair_-bosch-.htm
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This may help you determine if the problem is the starter:
http://w6rec.com/duane/bmw/starter/index.htm
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...Checked pricing on starters. Ouch. 300+ from Bob's. about 200 from motobins. Any other resources that people can recommend...
Don't throw money at a starter right now. Continue checking the simple things until all are either eliminated as problems or fixed.
When I return home on Monday, I'll post a link for starter rebuild kits... unless someone else reads this and does so. But doubt it's the starter.
Right now, I'm in Luckenbach, wrapping up another great Harvest Classic. So many great vintage bikes of all flavors.
I hope you are taking pictures/videos
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Ok odd enough started up great today at 50 degrees after a trickle charge for a few hours. I'll try and get video in a few days when it hopefully dries up. Rainy season is upon us up here.
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As a side seems more electrical between the charge helping today and the smell of gas when it wouldnt start yesterday. Really I need to get a multimeter to test the battery and coil before I do any more trouble shooting. Thanks again for all the feedback.
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Here's the link I have you, if ever needed:
http://www.euromotoelectrics.com/category-s/47.htm
Good source for BMW bits.
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Here's a curious sideline. My 79 used to start and run up instantly with no choke at all, even in cold weather. And fuel consumption was slightly high. After a couple of years I cleaned out the flat-top carbs and found that a PO (it's always a PO, isn't it?) had bent down the float tabs which raise the needle on both. So raising the fuel level in the float bowls. I fitted new floats, pivots and needles - result better fuel consumption but starting rather like aarm's complaint. The engine will start quickly but only with idle screws about 2 turns out, and will not run up for about 30 seconds - before that, opening the throttle causes it to die. On the road, it's fine. I suppose the PO was worried about starting.
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~By the way I was in Galveston, Texas last week. Good to see quite a few bikes around. Not so good that they were all Harley-Davies, real or fake. No BMs.
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Shame our Bings don't have old fashioned ticklers so we could flood the carbs simulating constellations high fuel level. Except for the smelly finger syndrome it wasn't a bad way of providing enrichment that automatically reduced it's effect once the bike was under way.
There are a couple of things I do in intermediate conditions when full choke is too much but the temperature is cool enough to need some enrichment:-
I turn the fuel on before taking the bike off the centre stand. I figure the floats have some inertia and have got to bounce when the bike hits the ground and let in a little extra fuel which will raise the level slightly. It's a small thing but it does seem to help. Perhaps because it ensures that any evaporation losses from the bike being stood are made up. If you think about it the floats can't possibly maintain the same level in the float bowl when it's stood still as when it's bouncing down the road. So you could have a slightly low level due to evaporation losses without the floats letting in any more fuel.
Another technique is to apply full choke and just fleetingly press the start button. This will pull some extra fuel through the carbs. I then turn the choke off and start as normal.
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Right Barry, the Amal tickler was one of the few features of the old Brit bikes that I still miss badly. It was a simple, brilliant starting aid and it meant that with all my old old Brits (1956 on) I never once had to use the choke for starting. (We called it the air slide.) A quick push on the tickler did it all, and no need to turn it off.
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~By the way I was in Galveston, Texas last week. Good to see quite a few bikes around. Not so good that they were all Harley-Davies, real or fake. No BMs.
Wish I knew about your trip. Got a good motorcycle friend -former resident of my village- in Galveston I could've hooked you up with. Knows plenty of good eating joints that aren't so tourist pricey.
You have family on the island?
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Close by. My brother-in-law, retired process engineer in oil industry, lives in Houston. He has a daughter lives with her family in Austin and they just bought a small house in Galveston, 2 mins. walk from Seawall. Holiday home, or maybe for rental, they don't know yet. But went there with the whole crowd for 3 days. It was very warm at that time! House still almost empty, lot of sleeping on airbeds etc. If you know the city, it's on Avenue T.
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Quite a hike to get to Texas. Houston is a 9-hour flight from London. Squished into economy class seat apparently designed for midgets, and I'm 6 ft 4 ins.