Honda CT110 COLD START and carb tuning adventures [Part 2 of 2]

[@martinrea8548]

Nice and clear. When do you know you have the right idling speed, and what are the downsides of having it too fast? If you adjust for fast idling will that also make your bike faster when riding. Thank you 🏍

[@stiffysworkshop]

Hi Martin! The postie bike uses a centrifugal clutch which means it's activated automatically by engine rpm - more engine rpm equals stronger clutch engagement. If the idle rpm is too high then the bike will try to drive the rear wheel while you're off the throttle at a stop - not very fun! There are ways of measuring the idle speed electrically and setting it to Honda specifications, but I don't have those tools. The correct rpm for me is between where the bike will happily idle without stalling (this sets the minimum rpm I'm happy with) and where the clutch tries to drive the bike (this sets the maximum idle rpm) I think setting your idle on the higher side will probably help you take off faster but it could hamper the top end by making the mixture too rich and not burning effectively, although I haven't tested this. Thanks for the comment!

[@martinrea8548]

@@stiffysworkshop Wow! Thanks so much for the great explanation. I just did my first bit of motorcycle maintenance today, and I'm delighted that I've solved a problem I've had for the last few weeks. I have a Honda Cub 90. It has 40,100 miles on the clock but is still in good condition and I use it for short trips around town. Well, after about twenty minutes it used to splutter and bog whenever I gave it throttle. I was down to 25mph max in third and had to change up really fast to get going at all, meaning I was going up hills in third. Very frustrating! I took it to a garage for them to service it, but they were too busy and not really interested so I decided to have a go myself. I changed the spark plug, cleaned the fuel outlet and then adjusted these two screws. I was going to tackle the valve clearances too but didn't have the feeler gauge needed. Anyway, whatever I did seems to have worked because she's flying again, maxing at about 50mph and lively in the full range of the three gears as well. It's very satisfying to get a result like that, Love those little postie bikes; I'd say they have a lot in common with the Cubs. anyway, lovey "meeting" you and thanks again for the content, input and reply.

[@stiffysworkshop]

Great to hear you've got your bike running so well! 50mph sounds very impressive for a 90cc! They are very satisfying things to work on, CT stands for trail cub so our bikes are definitely cousins 🙂 Nice to meet you also, enjoy that cub!

[@caxx.g]

I can move my mixture screw not even a quarter turn and it throws it out of wack

[@stiffysworkshop]

Have you cleaned the little fuel filter in the carb recently?

[@caxx.g]

@@stiffysworkshop was charged $240 for a tune because I wanted a professional tune, $80 was for a new carb house. Ended up pissing fuel couple days later so now im just doing it myself. I doubt its even a new carby. Ill check the fuel filter

[@stiffysworkshop]

@@caxx.g sorry to hear that 😬 Pretty sure I did a vid on doing a postie bike carb tear down, clean, and rebuild. It's very step by step but might help

[@stiffysworkshop]

@@caxx.g kzbin.info/www/bejne/oZfEho2pncSfasU

[@caxx.g]

@@stiffysworkshop i beat you to it