Robin Posted October 17, 2022 Posted October 17, 2022 Can anyone here offer advice on adjustment of the standard carb. for a Honda Dream 125. Ous is becoming difficult to start and keep running on these colder mornings. My feeling is that the tick-over mixture needs to be riche and the tick-over faster, but how to do this. I would expect there to be a mixture screw adjustment and a tick-over speed adjuster. If i could see a picture to the carb with these two adjuster identified, I should be able o set it up to run better fort thing. Any assistance welcome. MY Thai is rudimentary and not up to explaining to Honda mechs., and wife's tech knowledge not up to knowing what I am on about. She just complains it 'won't start properly' "knowledgeable" local has told her to change the oil.
papa al Posted October 17, 2022 Posted October 17, 2022 √ carb adjustment vids on Youtube. Is air filter clean.? Fuel filter.? Choke inadvertently engaged or not.? How old is bike. Maybe carb cleaning is in order. 1
Kwasaki Posted October 17, 2022 Posted October 17, 2022 If you can't do Carb work yourself ask around locally for a motorcycle bike mechanic who knows about carburetors. We have several guys who have small workshops who are capable of sorting bike carbs out in our area.
In the jungle Posted October 17, 2022 Posted October 17, 2022 I have a 2001 Dream 100. Idle screw (tick over) is the larger of the two screws and protrudes from the carb. Mixture screw is smaller and flush with the body of the carb. On my bike setting it up does involve a compromise. If I set it up so that it idles when the engine is cold the idle will be too high when the engine is warm. If I set it up so that it idles correctly with the engine hot then it will not idle when the engine is cold. The way I have it set up the engine will not idle from a cold start but it is fine after two or three minutes running. When hot the idle is slightly higher than I would like. I spent quite a bit of time messing around with different settings and that was the best compromise. 1
In the jungle Posted October 17, 2022 Posted October 17, 2022 I should add that I have owned the bike from new and it has always had this characteristic.
Popular Post VocalNeal Posted October 17, 2022 Popular Post Posted October 17, 2022 As stated above the idle speed screw is the one with Phillips head. The slow speed air/mixture screw is the slotted screw. With the engine warm turn in the Phillips screw 1/8 turn and speed up the idle a bit. Then screw the air screw in 1/8 turn at a time until the engine speed increases, if it doesn't turn the screw out 1/8 until the idle increases when you have the idle at its maximum turn the air screw in 1/8 until the engine just starts to slow down. Then turn the phillips screw out in 1/8 increments until the idle returns to normal. Note : Idle speed for these engines is quite high at about 1500-1800 rpm. Not a slow phut-phut-phut. Then go to Shell and fill the tank with Shell VPower 95 and let that run through the system over time. Can repeat if you want. VPower has extra additives for cleaning as does Bangchak S91 or S95 2 1
Kwasaki Posted October 17, 2022 Posted October 17, 2022 1 hour ago, In the jungle said: I have a 2001 Dream 100. Idle screw (tick over) is the larger of the two screws and protrudes from the carb. Mixture screw is smaller and flush with the body of the carb. On my bike setting it up does involve a compromise. If I set it up so that it idles when the engine is cold the idle will be too high when the engine is warm. If I set it up so that it idles correctly with the engine hot then it will not idle when the engine is cold. The way I have it set up the engine will not idle from a cold start but it is fine after two or three minutes running. When hot the idle is slightly higher than I would like. I spent quite a bit of time messing around with different settings and that was the best compromise. The compromise setting also excludes the choke with carbs whether is auto choke or choke cable. 1
VocalNeal Posted October 17, 2022 Posted October 17, 2022 In Thailand one probably doesn't need the choke but it could be stuck in the wrong position through lack of use. Both my bikes are FI and the scooter does smell a bit rich when it is first started so it is applying "choke" automatically.
Kwasaki Posted October 17, 2022 Posted October 17, 2022 20 minutes ago, VocalNeal said: In Thailand one probably doesn't need the choke but it could be stuck in the wrong position through lack of use. Both my bikes are FI and the scooter does smell a bit rich when it is first started so it is applying "choke" automatically. Most times in my car port the bike engine always needs choke by cable to start but it has to be close gradually almost straight away until the engine is warm. My carbs would be running rich if it didn't need choke. My airblade is on auto-choke everytime I start it for about a 100metres.
In the jungle Posted October 17, 2022 Posted October 17, 2022 The Dream 100 I have has a cable operated choke. I have verified that it is fully off when the bike is running. In fact I have never use the choke in any circumstances in 21 years. 1 1
Kwasaki Posted October 17, 2022 Posted October 17, 2022 11 minutes ago, In the jungle said: The Dream 100 I have has a cable operated choke. I have verified that it is fully off when the bike is running. In fact I have never use the choke in any circumstances in 21 years. Running rich which is not big problem with small engines.
LS24 Posted October 17, 2022 Posted October 17, 2022 Has the spark plug been changed or at least checked? The issue could be that it is already too rich at start up. 1
In the jungle Posted October 17, 2022 Posted October 17, 2022 1 hour ago, LS24 said: Has the spark plug been changed or at least checked? The issue could be that it is already too rich at start up. I am not sure if that question is to me or the OP. If it is to me then I stay on top of maintenance well by spreadsheet. Spark plug gets swapped at 10K max. Fuel filter also gets changed regularly. Carb only gets stripped and cleaned if problems appear. Bike gets almost daily use.
Adumbration Posted October 17, 2022 Posted October 17, 2022 10 hours ago, papa al said: √ carb adjustment vids on Youtube. Is air filter clean.? Fuel filter.? Choke inadvertently engaged or not.? How old is bike. Maybe carb cleaning is in order. Check all of the things that papa al has suggested. But also make sure that you check the two bolts that mount the dream carby to the intake manifold. They can work loose and cause air to enter the manofold between it and the carby. Check that the gasket there is also intact. If you are sucking air that will cause the problems you describe.
In the jungle Posted October 17, 2022 Posted October 17, 2022 22 minutes ago, Adumbration said: Check all of the things that papa al has suggested. But also make sure that you check the two bolts that mount the dream carby to the intake manifold. They can work loose and cause air to enter the manofold between it and the carby. Check that the gasket there is also intact. If you are sucking air that will cause the problems you describe. Thanks for the suggestion. On the Dream I have there are O rings either side of the inlet manifold. I have replaced them before but that was 130,000 km ago at 80,000 km. Will look at them again.
stubuzz Posted October 17, 2022 Posted October 17, 2022 Depending on the mileage, a carb rebuild or a new unit would be beneficial. https://shopee.co.th/คาร์บูเรเตอร์W100s2005แท้-i.511164838.5497428225?sp_atk=49d6fc42-264c-4004-ab81-880885a17dd0&xptdk=49d6fc42-264c-4004-ab81-880885a17dd0
papa al Posted October 17, 2022 Posted October 17, 2022 3 hours ago, In the jungle said: I have replaced them before but that was 130,000 km ago at 80,000 km. Will look at them again. Should be good for 150,000 km so no hurry.
papa al Posted October 17, 2022 Posted October 17, 2022 hmm 14 hours ago, Robin said: is becoming difficult to start and keep running on these colder mornings. 14 hours ago, In the jungle said: I should add that I have owned the bike from new and it has always had this characteristic. 7 hours ago, In the jungle said: In fact I have never use the choke in any circumstances in 21 years. Sounds crazy, but maybe try using the choke for cold start-ups. That is its exact purpose.!
In the jungle Posted October 17, 2022 Posted October 17, 2022 4 hours ago, papa al said: hmm Sounds crazy, but maybe try using the choke for cold start-ups. That is its exact purpose.! You could be right. I will give it a try. Nothing ventured, nothing gained. 1
In the jungle Posted October 17, 2022 Posted October 17, 2022 7 hours ago, stubuzz said: Depending on the mileage, a carb rebuild or a new unit would be beneficial. https://shopee.co.th/คาร์บูเรเตอร์W100s2005แท้-i.511164838.5497428225?sp_atk=49d6fc42-264c-4004-ab81-880885a17dd0&xptdk=49d6fc42-264c-4004-ab81-880885a17dd0 I am not convinced as to replacement. I have never had to replace a carb in nearly 50 years of riding/driving. Why throw away a perfectly good carb. That is a good price on that carb but if buying I would need to check it was the correct spec as often there are periodic minor changes. Mostly carbs are replaced here because some idiot has wrecked the thing. I avoid that by working on all vehicles I own myself. Last time all carb gaskets and seals were replaced was 130,000 km ago but it is only about half an hour to strip and check the carb so I will do that.
papa al Posted October 18, 2022 Posted October 18, 2022 2 hours ago, In the jungle said: You could be right. I will give it a try. Nothing ventured, nothing gained. Lube.
In the jungle Posted October 18, 2022 Posted October 18, 2022 7 minutes ago, papa al said: Lube. Carb does not need lube. Both cables work perfectly (throttle and choke). 1
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