Thunderchild Posted June 30, 2012 Share Posted June 30, 2012 I have an XVS 125 (54 plate, 6.5k). I was out riding the other week and she started to lose power when doing 50mph. It only lasted for a second like the brake was on, and then continued as normal. This repeated a couple of times during the journey. I have replaced the oil and filter and put new plugs in to see if it helped. The old plugs looked like originals and appeared black at the ends, one was slightly wet on the thread. On the way to work, she did the same thing again when I got her in to 5th gear. It was an extreme downpour at the time and I initially thought this may have been contributing to the problem and the engine was not warmed properly. However, when I pulled out the car park after work, she died completely in first gear with a total loss of power. When I opened up the throttle, she would pull off, the power would drop and eventually she would cut out with the throttle fully open. I noticed that there was a point on the throttle before she lost power, so I had to hold that position and change gear quickly to let the speed build up. I eventually managed to get her into third and limped her home doing 15-20 mph. When she is in neutral and I apply the throttle, she revs normally, reaches a certain point and the power/revs die off. I can continue to open the throttle fully with no difference and she will just cut out. Now my first thought was she was losing compression and it could possibly be the rings. Having searched through the forum, I came across this thread: I have checked my carb manifold and it appears to have a small crack in it and a bulge just above left of the crack (see pic). It doesn't open up when I rev her in neutral, but could this be the problem or is it something else? Many thanks. Link to comment Share on other sites More sharing options...
Thunderchild Posted July 2, 2012 Author Share Posted July 2, 2012 Just a thought before I pay out for a new carb joint. Could I test it to see if it is the problem by using some high temperature RTV sealant like gasket seal, to see if it improves the issue? Link to comment Share on other sites More sharing options...
dt502001 Posted July 2, 2012 Share Posted July 2, 2012 Eng's don't loose compression and regain compression,if it were ring's she would be smoking, sounds more likely that your not getting proper fuel flow. you should pull the fuel line off the tank and see that fuel is flowing freely ,drain the carb bowls and check for dirt in the carbs. I have never worked on a 125 dragstar but if it has a fuel pump check the volume of flow commin to the carbs. And yes you could use sealer to try but that crack dosent look bad enough to cause all this and it would not come and go it would be the same all the time. Link to comment Share on other sites More sharing options...
Moderator Airhead Posted July 2, 2012 Moderator Share Posted July 2, 2012 as a temporary measure you should just be able to wrap the suspect area with PVC electricians tape shouldnt you? just in order to prove the theory Link to comment Share on other sites More sharing options...
AndyBuk Posted July 2, 2012 Share Posted July 2, 2012 This might sound daft but have you checked the throttle cable to see if its splitting, I had a similar problem in the past, broke down andd the AA came out and changed the cable. Link to comment Share on other sites More sharing options...
Thunderchild Posted July 11, 2012 Author Share Posted July 11, 2012 Thanks for all the feedback. I've been working my way through your suggestions (in between rain and work), and have decided to strip the carb and clean it out. So, I'm ok taking everything off to get to the actual carb, but I've never removed one of these before and it seems to have lots of cables and pipes (I say lots, more than I thought it should have). Other than photographing everything before I start and during, can anyone offer advice about removal and cleaning the carb before I go any further? I think the only way to learn is to do it and I'd rather learn than pay a mechanic to do it for me. Cheers in advance : ) Link to comment Share on other sites More sharing options...
Thunderchild Posted July 20, 2012 Author Share Posted July 20, 2012 Having had trouble starting her up, she finally started this morning and I took her for a spin. Having cleaned out the air filter, she is still bogging but nowhere near as bad as before and actually feels like she wants to go but can't. Since I now have a workshop manual, subject to weather, I'll be cleaning out the carb this weekend and checking the fuel lines. Link to comment Share on other sites More sharing options...
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