'94 1500 trike transmission slipping?

[ironman218]

trike has 115,000 miles and when I try to climb a steep grade the transmission kicks out of gear for a moment, I back off the acceleration, the transmission kicks back in gear. If I approach the hill at a speed of 55-60 mph I can usually make it to the top with no problems, provided I do not try to accelerate to a higher speed. If I approach the hill at 35-45mph that will be my top speed all the way up. Any attempt at accelerating only causes the transmission to kick out of gear momentarily. I am looking to put the trike into a local bike shop but was hoping for some ideas as to what might be causing the problem. Any help is appreciated.

[WingAdmin]

Do you have a heel/toe shifter by any chance?

Do you often shift without using the clutch?

[Rambozo]

Is it the clutch slipping, or does the transmission pop out of gear into a false neutral?
Does it happen only in high gear or all gears?

[Andy Cote]

When did you last change the oil and what brand did you use? I'm with RAMBOZO here. The transmission doesn't slip and if fifth gear is not fully engaged, it can jump out in to a false neutral but doesn't jump back in when power is removed. Time for a new clutch.

[WingAdmin]

The reasons for the questions I asked:

Heel/toe shifters can cause excess force to be applied to the shift forks, bending them. When they get bent, they don't push the gear dogs fully into engagement, so they can pop out under load.

Shifting without clutch causes excessive wear on the gear dogs, rounding off their corners and causing them to pop out under load.

[ironman218]

Sorry it took so long to get back. I use GN4 10-40W and changed it this spring. However the issue has been with me since buying the bike back in 2016. I do not know if the previous owner shifted a lot not using the clutch, but I have been guilty couple of times with me when downshifting, then scolding myself for not paying attention. Yes, I do have a heal/toe shifter. I've waited till today to take the trike out and duplicate the problem. Riding up a slight grade in fourth gear, I wound the engine up to 46 mph and it again repeated the problem. Gently easing off the throttle the trike re-engaged in fourth gear and this time I noticed I was able to pick up speed to 50 mph. I then engaged OD and continued to increase speed to 60 mph. The speed limit being 55 I chose to slow down. Normally the problem happens when in OD, climbing a steeper grade hill and trying to increase speed. Regular highway riding is great, only when I approach a steep grade do I run into an issue. I do appreciate your feedback, I have learned some good thing from Goldwing Docs over the past 5 years. Thanks again.

[Rambozo]

What you describe is clearly a clutch issue. The first thing to check is that the tiny return hole in the master cylinder is not plugged. Cycle the clutch a few times, then with it released, crack the bleed screw and see if there is any residual pressure. If you're lucky it's a hydraulic problem, and the clutch might be salvageable. If not, you're looking at a new clutch.

[WingAdmin]

What you describe is clearly a clutch issue. The first thing to check is that the tiny return hole in the master cylinder is not plugged. Cycle the clutch a few times, then with it released, crack the bleed screw and see if there is any residual pressure. If you're lucky it's a hydraulic problem, and the clutch might be salvageable. If not, you're looking at a new clutch.

It could be clutch, but it is also a classic symptom of rounded/worn gear dogs and/or shift forks (preventing full dog engagement), which is why I asked the questions I did.

[Rambozo]

What you describe is clearly a clutch issue. The first thing to check is that the tiny return hole in the master cylinder is not plugged. Cycle the clutch a few times, then with it released, crack the bleed screw and see if there is any residual pressure. If you're lucky it's a hydraulic problem, and the clutch might be salvageable. If not, you're looking at a new clutch.

It could be clutch, but it is also a classic symptom of rounded/worn gear dogs and/or shift forks (preventing full dog engagement), which is why I asked the questions I did.

Very true. But I would expect a more violent description with the dogs not engaging, including some jerking and noise. That's why I asked about other gears, and when he confirmed that it happens in fourth and fifth and no mention of noises, I would go with clutch. Any competent mechanic could take it for a spin and instantly know just what it is, but doing it via written descriptions over the internet is always a challenge.