I'm having a problem with my second Vision where if I ride the bike for 10 miles at about 40 - 45 mph it has a tendancy to heat up to the point where the temp gage is right on the verge of the read zone. If I get to an open stretch of road and then push it up to 60 mph it cools right down to where the temp gage is right in the middle again.
I've taken the radiator off and flushed it, I removed the right side cove and checked out the waterpump. I filled the coolant from the bleed screw under the tank. I tried one of those super coolant additives. I even burped the system a number of times just for good measure but the problem still remains. I haven't replace the thermostat but it doesn't sound like a thermostat problem.
Any ideas?
Have you checked that the fan works? Checked the fuse for the fan motor?
No that's one I didn't check the fan. If the fuse is good I'll hotwire it to make sure the fan works. I was considering putting switch in line to override the thermostatic switch if I'm stuck in traffic. I did this on my first V years ago.
Thanks
Quote from: VisionaryDan on May 19, 2006, 01:03:49 PM
I haven't replace the thermostat but it doesn't sound like a thermostat problem.
I think it does. Try pulling out the thermostat and see what happens (I have been running w/out one for the last 30k, and my bike never goes more than 3/4 of the way up the temp gauge)
out of sync carbs will get'cha hot too. I know it does >:( >:(
sounds like a stuck thermostate. at low engine speed theres lower pressure. higher engine speed means higher pressure. the bypass built into the thermostate will only open under higher pressure (keeps you from building too much pressure) also if the thermostate is in backwards it could also cause this problem. since youve had it all apart are you sure you put the theromstate back in the right way. pull it out. check it on the bench (should tell you how in the manual, heat water to certin temp pop thermo in and see if it opens)
ill bet its either in backwards or is bad.
PS2 the reason I pulled it all a part was because of this problem - I'm sure I put it back the way I found it. I've worked on too many cars to make that mistake.
I guess that's why I didn't think it was the thermostat. Because in a car driving it faster wouldn't have done much to cool things down. If your thermostat was stuck closed in a car you won't get very far.
Pulling out the thermostat in the V was something that I had given some thought to. I may just try that for a while - especially if it helps to keep the engine running a little cooler.
As far as out of sync carbs - that's something I should do. Generally though the bike runs good, a slight stumble now and then but nothing horrible. I should really tear down the carbs and rebuild them before I spend the time to sync them. But nows not the time to work on it - the weather is too nice.
Thanks
:) Have you checked the thermo unit.... ??? this fires up the fan when the temp' rises.... ;) This unit is located coming off the top rad' hose, down from the coolant "bleed unit". There are two unit's, the lower one is the thermo unit (Yamaha part #11H-83591-00-00....I'm sure this is right). However, make sure that its connected/connection is clean. Seeing as you have to remove it to test it...and its 20+ year's old....and you have changed the coolant, flushed the system, etc......spend a few dollar's on new part's and throw it and the thermostat in the garbage..... 8)
I also loosened up my valves a bit (.05 to .1).
Quote from: VisionaryDan on May 19, 2006, 04:42:23 PM
I should really tear down the carbs and rebuild them before I spend the time to sync them. But nows not the time to work on it - the weather is too nice.
You can build the manometer and sync the carbs in about 10-20mins, it's reall REALLY easy, and more than worthwhile.
this may sound stupid, but been burnt by this before,,,check the rad cap and make sure it is holding proper pressure, because that will affect boiling points, last thing to check if everything else seems to be working properly
Hey back to the carb sync solution. Could carbs being way out of sync cause the engine to kick back when trying to start? I've also been having a problem where the starter clutch can't seem to hold when cranking and I get a bang or grind. Could the two problems be related?
This bike typically this bike is hard to start and is much worse on gas than my other Vision. I have made a home made manometer but never had much luck with it. No matter what kind of oil or fluid I used in it it would tend to foam up and get air bubbles in the line. I was able to get my other Vision close with it but I finally took it to the dealer. After they sync it I was a noticable difference.
Dan
I'm not sure about the kick back, but the gas mileage would make sense.
When I first made the manometer, the tubing was too big and I used ATF fluid
I redid it with smaller tubing (3/16"id?) and used 15w fork oil. much better.
Both times I got 20' of it and had about 4' of run for the fluid. you only need to fill the fluid up around 12 or 18".
The meter is VERY sensitive. any sudden adjustment can result in the fluid being sucked in (hence the thicker fluid).
If it's way out, you should get it close first by ear and "vibration". When she runs pretty smooth (and cool) you know you're close.
OK I'm a blind. The fan was unplugged - how it got that way who knows?
So I decided to mess with the carbs anyway. I actually had it running great, no stunble, quick acceleration and then I decided that I wasn't happy with how long it took for it to settle back down to an idle. This was all by ear granted and now the stumble is back and the snap it had accelerating isn't quite there, its running about the same as it had been now. I really need to dust off the home made manometer and give it a try. Either that or I'll give the local bike shop a a shot at it. They did a great job on my other Vision.
Dan
Quote from: VisionaryDan on May 23, 2006, 08:32:31 AM
had it running great... then I decided that I wasn't happy
been there! I messed em up pretty good and had the slow return to idle syndrome. After I got the sync set right, it was gone. (I know my yikes is tight and vacs are good). Might be worth a trip to the dealer if he did you right the last time. If they can tune the carb pilots by the CO numbers, I think that'd be even better
A slow return to idle could be a leaky YICS. Check the YICS for both internal and external leaks.
Well it isn't the YICS since I have replaced on both bikes with the home made copper tubing version last year. The dealer setup the carbs with that modification last year and didn't say a word. It goes in the shop Tuesday if I can get the thing running smooth enough to ride 20 miles. We'll see hao they do this time.
Thanks,
Dan