Bike wont rev

Crau

XS400 New Member
Messages
4
Reaction score
0
Points
1
Location
Sweden
Hello, new rider here and really new to any kind of troubleshooting and fixing motorbikes.

Just got a -83 12E a couple months ago which started and ran fine. Have been riding perhaps 60-100 km on it without any real problems.

Was on my way to go out riding with a couple of friends for the first time but only got about 1km before it started to behave weirdly. Nothing happened when turning the throttle and it slowed down to approx 10km/h and managed to get it half way back home in that speed before it died completely and wouldnt start.

Tried starting the day after and it turned over and idled fine, think i even could get it to rev on first gear for some time before it went back to not revving.

Been at a mechanic with the spark plugs and they told me it looked like they ran lean.
Already changed fuel filter but that, didnt do anything. Im thinking next step is to check if the carbs are synced, then clean them and change spark plugs. Does that sound like a good start?

Been browsing this forum for a week now, learnt a lot about my bike and seen that theres a lot of experienced people on here who seem to be happy to help out:) Cant begin to work on the bike until next week so just thought I would make this post first to see if anyone has any other advice.
If someone has any good online shops located in EU that would be great as well, Mikesxs seem great but the shipping was a bit expensive outside US.

Heres a video of the bike idling and at the end you can hear how it sounds when throttling as well.

 
It sounds like my bike when I forget to turn my petcock on about a mile down the road. Maybe the petcock screen has crud on it? Does it run better if you switch it to reserve?
 
It sounds like my bike when I forget to turn my petcock on about a mile down the road. Maybe the petcock screen has crud on it? Does it run better if you switch it to reserve?

Wow, quick reply!

Think i tried runnning it on prime, but not reserve. I'll try with the reserve as well.

Thought about going through the petcock if the carb clean wouldnt help, but perhaps the petcock would be a better first step? You suspect it doesnt get enough gas, right?
 
It certainly could need a carb clean, or a stuck float, but it sounds more fuel related to me. Others will certainly chime in.
 
It certainly could need a carb clean, or a stuck float, but it sounds more fuel related to me. Others will certainly chime in.

All right, Thanks!

I replaced the fuel filter with a clear one, so i can see that fuel gets through the filter on prime at least.
I will go check on the bike today, probably will come back with more questions aftee that :)
 
Sounds to me like a fuel flow issue and not ignition related. So, I think checking the tank for debris, a petcock clean/rebuild and then carb clean/rebuild would be my plan of attack in that order.
 
Sounds to me like a fuel flow issue and not ignition related. So, I think checking the tank for debris, a petcock clean/rebuild and then carb clean/rebuild would be my plan of attack in that order.

Ok, thanks!

I was checking in on the bike yesterday, changed Spark plugs, looked for air leaks but also checked the fuel flow by loosening the fuel hose from the carbs. On pri it seemed to flow ok, wouldnt that rule out the petcock or could it be worth to checkout anyway?
 
Back
Top