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I posted about this some time ago, a few years back, and am still having the same problem.

If normally accelerating, not punching it just going with the flow, there is what I will describe as a "lurch", only in 2nd gear, at 20 - 25 mph (30 - 40 kmph for us in Canada)

If I stay at that acceleration level in 2nd to 40 mph (60 kmph) it happens again. It is important to note that if I slowly accelerate in 2nd I can go past 40 mph with no lurch, however I have to be quite slowly accelerating.....too slow.

There is a knocking, or metallic sound when this happens. If I have a passenger behind me, she will hit the front of her head against the back of mine.

To avoid this I shift low in 2nd gear to 3rd, dogging it way too much but avoiding the lurch.

2009 VN1700

I JUST made the following replacements/upgrades:

  • The exhaust, which I had debaffled, with a full Vance & Hines Big Shot (love the sound now!!)
  • Added a Power Commander
  • Alley Cat Air Cleaner with K&N Filter
These changes did not affect the lurch however I love them! Also added a light bar and passenger floorboards.......jussane.

I'd appreciate any thought you have or suggestions. Many thanks.
 

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Sounds like a transmission issue. Remember the 2009 and 2010 Vucan's had straight cut gears for 1st and 2nd. Might not be engaging all the way slipping out and back.
 

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This is pretty straightforward for me to diagnose.

You have a very common motorcycle transmission problem. What is occurring is when enuff tork is applied when in second gear the 2 gears associated with second gear will separate.

M/C trannys are what are called "constant mesh" which means all gears, in the case of a 6 speed tranny, are in "tooth mesh". The 6 gears on the input shaft and the 6 on the output shaft are meshed tooth to tooth. Gear changes are accomplished by sliding one gear sideways so that it meshes with it's neighboring gear via any combination of protrusions (called "dogs") and/or slots on the sides of the gears.

The contact area of those dogs and/or slots is relatively small and as those contact areas wear the ability for the gear to stay in engagement is lessened. What is happening is the sliding gear which is held in it's position by the shift drum and shift fork gets "pushed out" of engagement. Since the shift drum has the shift fork in that position the fork bends away as the gear moves out of engagement, but the fork acts as a spring and pushes the gear back into engagement. This can occur a multitude of times or just once, every gear failure is different but the characteristics are the same. Thus your "lurch/skip" scenario.

The engine will have to be removed and torn down to gain access to the tranny. The gears associated with second gear will have to be replaced along with the shift fork and shift drum.

As a recommendation I would suggest having the new gears "undercut" to minimize this happening again. If there is any wear on the rest of the gears have them undercut at the same time. I have been undercuttung gears for bout 20 years and it is a sure fire way of improving tranny longevity.

RACNRAY
 

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I had the same issue with my 2009, although it didn't occur until 350,000 kms and gradually got worse until I pulled the engine at 403k. As Ray described, the gears are worn and/or shift fork is bent. It is caused somewhat by normal wear and tear but more likely by sloppy 1-2 shifting, applying power before second gear is fully engaged. This almost always shows up on second gear because it is a 'long and clunky' shift compared to the other gear changes.
Unfortunately, the only way to repair this is to remove the engine/transmission and completely disassemble it, and if done at a dealer could easily cost $2500-$4000. For me it didn't make sense to spend that much money on a transmission that was hooked to such a high mileage engine so I found a low-mileage engine/trans from a wreck and i'm good to go for another 400,000 kms. Used engines for Japanese cruisers are very reasonably priced (compared to used HD and sportbike engines).
 

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I got rid of my 2009 1700 for the same reason...sold it to a Harley dealer. He sold it to another person near me and now I see it for sale on Craigslist. It was a pretty bike but ran like crap...
 
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