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need some help with a 1981 honda cb900 costom wont start

Posted: Sat Apr 03, 2010 4:34 pm
by stickyhand45
Hi I Need some help with a 1981 honda cb900 custom it won't start
i Bought It Off a Friend Its was Running Good two summers ago for him.. Now i Bought It Off Him As It Would not start for him be took it to his brothers Harley shop and they cleaned the carbs..then he took the the bike to me and said.. i need to get the carbs Syncing..because the guys at the Harley shop don't have the tools to do it..Anyway i tried to start it and click click the starter was gone..So got a new Starter and it Started i gave it gas and it backfired a few times..and bogged out while giving it gas.it seems like it is getting to much or not enough gas its fires but don't start.Can some one tell me what could be wrong or how i can fix it thanks for the read.

Re: need some help with a 1981 honda cb900 costom wont start

Posted: Sat Apr 03, 2010 5:59 pm
by Johnj
I suggest you get a service manual for your bike. Syncing the carbs is quite involved.

Re: need some help with a 1981 honda cb900 costom wont start

Posted: Sat Apr 03, 2010 6:27 pm
by stickyhand45
so you thinks its the carbs not the valves?
Anyone else and any suggestions?

Re: need some help with a 1981 honda cb900 costom wont start

Posted: Sun Apr 04, 2010 1:30 am
by HYPERR
stickyhand45 wrote:so you thinks its the carbs not the valves?
Anyone else and any suggestions?
If it was running fine before the guy parked it two years ago, and nobody has messed with the valves, it is highly unlikely that the valves loosened or tightened that much.

I would suspect it's the carbs. This Harley shop does not have a gauge to sync the carbs??? I understand that HD's are twins and only have one carb, but you would think a legitimate bike shop would have it and be able to perform it in their sleep. Sync'ing cabs is not really rocket science. You adjust the vacuum on the #1, #3, & #4 carbs using #2 as the reference point. When they cleaned the carbs, did they say all the jets, etc were unclogged and in proper working order?

Re: need some help with a 1981 honda cb900 costom wont start

Posted: Sun Apr 04, 2010 3:09 am
by stickyhand45
Hey HYPERR thanks for the response..Yes they said the jets, so on where cleaned and ready to go..I just have the sync the carbs..i don't understand ether why they could not do the carbs its a big shop..i think they are not telling me or all BS..ill have to take it in to a shop..for Honda's i guess.. Its just a 3 month to get in they are so backed up..in was thinking i could do it but i don't have the skills on bikes..if there is anyone in Edmonton Canada can do it? ill pay cash..

Re: need some help with a 1981 honda cb900 costom wont start

Posted: Sun Apr 04, 2010 6:02 am
by Wrider
Yeah, I just spent a night of free time watching Tremors (Burt Reynolds FTW) and 30 bucks in parts to make basically the same thing as a $100 Motion Pro carb sync gauge and a $90 fuel bottle. They were feeding you crap.

Re: need some help with a 1981 honda cb900 costom wont start

Posted: Sun Apr 04, 2010 7:03 am
by Johnj
Here you'll find my instructions for making your own manometer. Your looking for a difference in the pressure, the fluid will move toward the bottle with the least pressure.

Re: need some help with a 1981 honda cb900 costom wont start

Posted: Sun Apr 04, 2010 9:53 am
by BuzZz
Hey Sticky, what HD shop did the work in your carb work? 'Can't sync the carbs' sounds like 'We don't want to bother' to me.

I've had good luck with these guys....
http://www.triplemmotorsports.ca/

They seem to be pretty good for getting work done from the guys I've talked to. But I do all my own work, so I can't say for sure. I buy a lot of stuff there and have talked to quite a few guys who have had them work on their bikes. They all claim to be happy with it.