Clutch slipping when accelerating...

Hi all - my 85 XJ700N is doing the above. I have heard that this is actually a "wet clutch". If so, should it be doing this? When I go through the gears, if I am trying to accelerate hard, the RPM's jump about 1000-1400, but the bike does not surge with power or accelerate - the bike stays with the same velocity, just the RPM's jump up. Then, when I let off the gas a bit, the RPM's come back down and the bike accelerates in the normal way. I don't know if this has anything to do with it, but it seems to have gotten worse as I turn in the pilot screws leaner... does anyone know what is going on? It also has a bit of "red light creep". Just trying to give the full picture...

 

Check the adjustment on your clutch cable. Both your symptoms are indicative of your cable being out of adjustment. Make sure you have some free play in the lever with the clutch engaged.

 

I'll give that a try, Stooge. Thanks -

 

What brand and weight of oil do you have in it? Additionally, how full is the case, up to the top fill line?
Remember, you want to avoid the EnergySaver grade oils. They have additive packages that will encourage slippage.

 

Robert - I have Advance Auto 20/50 in there right now. There was gas in the oil when I started working on the carbs, so I changed the oil and filter and put that stuff in there. I worked on the carbs a lot, including float adjustments and Pilot Screw adjustments, and I just wanted to make sure I didn't get gas into my Mobil 1 20/50 oil, which I intended on putting in once I KNEW that the carb adjustments were all done. Now, since I cannot seem to get "cobalt blue" on the Colortune and even have the Pilot Screws turned only 1/2 turn out and the bike still doesn't have power in the low end and still smells of running rich, I guess I may have to "suck it up" and just ride the bike "as is" for the remainder of the season - which means I should probably go ahead and change the oil and filter again and put in the Mobil 1 20/50.

 

...and yes, the oil is up to the top fill line... I just wish this bike would get dialed in! I took it out for a full day's worth of riding on Sunday - and could tell how much more fun it would be if the bike would run the way it wants to...

 

This might be of some use:

Colortuning the XJ

Are the float levels OK? Have you had the carbs apart and cleaned them?

Make sure the oil you are using does not have Friction Modifiers in it.

 

Yeah, the float heights are good - I just dismantled and cleaned them T-H-O-R-O-U-G-H-L-Y... and I will be changing the oil to my "good" Mobil 1 20/50 this week.

 

I also have an '85 XJ700N. My bike had the same clutch slippage concern as you have under hard acceleration. I had been using a regular automotive grade 10w-30. Drained that out and put in the recommended 20w-40 Yamalube and the clutch slippage is gone.

 

Thanks for that piece of info, Teewinot! I appreciate it - and will be hoping my follows suit when I change the oil and filter this week!

 

how did that work for you jeepdriver? i have the same issue and the same bike as you. i drained the oil and put in some yamalube and changed the filter. Still slipping. I want to order the cd so i can get a look at how technical the clutch replacement is, but got no response from the guy on email. Can anyone tell me what is involved in the clutch inspection/replacement on this bike and if you need special tools? i have replaced several vehicle clutches but never cracked the case on a bike. thanks for your help guys. by the way, the clutch cable is not too tight.
1985 XJ700N

 

If you have the pilots screwed only 1/2 turn out then there are other issues here. When you had the carbs appart did you remove the emulsion tubes. If so did they seat correctly when you reinstalled them. They only go in one way. They must be fully seated in order to work properly. Sounds like fuel is gettin past them or the needles and causing a rich condition.
OR
The enrichment circuit(AKA choke) is on partially. Check that on the carbs themselves not at the handle bar. The little forks that activate the plungers should be all the way down when the choke is in the off position.
Either of the above will cause a rich condition. Plus more but that seems to be the most common.
As for the clutch issue. Either cable adjustment on the oil is your best bet. Get that rich condition repaired befor putting in the moble one though.