Polaris ATV Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
10 Posts
Discussion Starter #1 (Edited)
I have a 95 Scrambler 400 that is having a hard time shifting into forward or reverse.
I used it to plow snow last month, and it would not shift into gear unless I turned off the engine.
I read somewhere it could be the ends are worn since it cannot shift into both forward and reverse.

I also noticed on the arm that the linkage connects to on the transmission has extra holes, and was wondering if I connected the shift shift assembly to one of the other holes I would get movement when shifting, and if this would resolve the issue. I disconnected the shift arm, and checked for wiggling, and I feel just a little bit.

Just wondering if someone had advice.
I attached pictures

IMG_20200101_114336952.jpg IMG_20200101_114434795.jpg IMG_20200101_114710678.jpg

If someone thinks it might be I just need new Rod ends, does anyone know if the rod ends from 1996 Scrambler would work?
I've checked for this part, the shift rod linkage on almost every polaris parts website I could find, and it looks like this part is never listed in any parts catalog for the 1995 polaris scrambler 4x4.
I found these part numbers: 7061014 and 7061013 from the 96 scrambler on ebay for $25, and it looks like they will work.
 

·
Premium Member
Joined
·
110 Posts
Could also be a clutch issue. Clutch alignment, primary clutch not fully releasing the belt, or the bearing in the primary starting to seize up could all cause hard shifting. (I'm not sure if your model ATV even has a bearing). If the clutches are trying to spin the transmission it will bind up the gears and be difficult to shift.

That would kinda make because you said it will shift if you turn the engine off.

To check this. Remove the clutch housing and start the ATV in nutral. Idling in nutral the belt should NOT be turning. If the belt is spinning something is wrong in the clutches.
 

·
Premium Member
Joined
·
3,907 Posts
More likely a clutch issue. Clutch drags the belt turning the secondary clutch input shaft and transmission.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #5
I was actually thinking it could also be an idling issue. I've always had a hard time getting it to stay idle. Cleaned the carburetor yesterday, but did not help much. So thinking may also need to do a compression test. Don't think this atv was maintained very well from the last owner. Thanks for the suggestions, it's helped. First get it idling well, then if still not shifting, will work on the clutch.
 

·
Registered
Joined
·
5,822 Posts
Most two strokes were not designed to idle, but some were - trials style motorcycles are not designed for high RPM performance, but for long periods of low speed operation and they idle exceptionally well.

Other styles of two strokes were not intended to idle at all - example; the 78 RM400 Suzuki MX bike had no idle screw on the carb (had a fuel mixture screw, but no idle speed screw).

Yes, if the compression is low, it will not idle well and if idle speed is elevated to increase compression, shifting will be difficult. It never ceases to amaze me how when a two stroke engine is renewed (re-ringed or new piston and rings and no other done) it idles higher immediately after rebuilding and the idle speed needs to be turned down.

An engine is an engine, but each design has it's quirks.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #7 (Edited)
Compression is 100, I think that might be a little low, but cannot find the specs in my Clymer manual.
Wet test brought it up to 110
 

·
Registered
Joined
·
5,822 Posts
I just scoured the Polaris manual and compression is not specified. It is recommended the compression be checked regularly and recorded so when compression starts to decline steadily the rings can be replaced before performance suffers.

Regardless of 'specs' - normal compression is between 120 and 150 with the throttle held wide open or the carb out of the holder. 100 indicates the engine needs inspected and worn parts replaced.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #9
Thanks, I did not have the throttle open, will have to try again tomorrow, but got a feeling it will at least need rings.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #10 (Edited)
105 psi with throttle open, and just remembered I am at 5000ft in Colorado, so maybe that is not bad. Will work on the idle and clutch.
 
1 - 10 of 10 Posts
Top