Disappointment with new V2 Sprockets

If anyone has followed my posts you know I am a devout believer in stainless steel sprockets but have just recently converted 1 drive to the new V2 plastic Sprockets.

I posted a few tricks and installation concerns in Roadrunner's thread announcing these new sprockets.

I had really high hopes, especially with the threaded brass insert. Not so fast.

After only about 6 or 7 uses the plastic sprockets are very worn on the sprocket shaft. They are so worn that the 1/8" gap normally seen between the drive spine and the sprocket guards is gone. The sprocket guards now touch and rub the drive spine, more so on the mast side. The scrape marks on the sprocket guards are evident.

Granted the bushings on the SS sprockets would also wear - but I could put 100's outings on them before replacement.

Here are the facts
My sprocket shaft is nearly new - got a new one 6 months ago.
I use turbo fins and do pedal quite a bit.
I assembled the V2 sprockets with small amount of marine grease.
I never beach my kayak with drive installed.
I adjusted the chains per Roadrunner's guide.

So now what? I like the fact that there is no mast wobble (like there is with SS & cotter pin) The plastic didn't break and the mast stay put. Drive felt very smooth and solid, until my last trip when the sprockets started to rub.

But - I'm not going to want to buy new sprockets every month.

Am I missing something? Was there a bad batch of these?

Something is definitely amiss! If I understand it correctly, your sprocket shafts are wearing and have enlarged about 1/8 inch within about 15 to 20 hours of use. I imagine this has also caused you to tighten the chain/cables to take up the slack.

Maybe there was a bad batch or it could be a lube problem. To give you a comparison, check out the sprocket - frame gap on this set:

As of today this Drive has logged approximately 549 miles (pedaling) in 137 hours on these brass insert sprockets. As you can see, there has been no collapsing of the sprocket-frame gap. I pulled the shaft after about 400 miles for a "how-to" post and regreased and rotated it 180 degrees. At that time, there was still diluted or thinned grease along the entire bearing surfaces. I use Breakfree to lube it about every 20 miles of use (which would have diluted the grease over time). I would have to say I'm not seeing much wear at all here.

If you compare the brass insert sprocket with the previous version, you will find that there appears to be no other difference in the sprockets:

In other words, your wear issue would not be attributable to the brass inserts, but with the plastic sprockets in general. This "hi glass nylon" material probably goes back another year, so it has established a pretty good track record.

I would be curious to see how much of your original grease is remaining and what the status is of your sprocket shaft. Try to get the dealer to exchange the sprockets under warranty (premature wear; factory authorized lube).

When you install replacement sprockets, rotate your shaft 180 to give you a new bearing surface, pack the assembly with ample grease and replace WD 40 with one of the friction modified spray lubes.

So if it turns out to be a bad batch, you should be set. Or if it ends up being a lube issue, you'll still be good. If it happens again, that's another matter.

A note on lubes -- I see that Hobie still recommends WD-40 "or equivalent" as a salt water lube. I'm no expert on this subject, but would agree with Fastfish that it is not a good lube for any pressure application. It appears to be essentially a kerosene based solvent from what I can find out. I like the stuff and use it as a penetrating oil and surface protectant, but not as a lube. I used to use it on the stainless sprockets, but WD-40 gets nowhere near my Drive these days. But that's just my opinion. Could it have caused your shaft wear? If there is no grease left in the wear portion of your sprocket shaft, it should provide some insight.

Yes, you understand correctly. The wear on the plastic sprocket where it rides on the sprocket shaft is so great as to have caused the sprocket guards to now rub on the spine. The nice 1/8 gap you see in your 1st picture is not there on mine. I have loosened the cables and verified the plastic sprocket wobble/wallow on the shaft.

There is still some grease on the shaft. I try to WD-40 the chains and not sprocket shaft.

When I rebuilt the drive with V2 sprockets I adjusted cables per your fine post/instructions. I left them a little looser than my original SS setup. Passed the RR performance with an A+ (grab pedals and let swing) After about 2 outings I noticed a lot of give in the pedals - almost like what one feels with the SS before they skip. Sure enough I needed to tighten the cables some - they got sloppy. Couple outings later the sprocket guard was rubbing the black wire ties used to hold the drive well seal. OK I fixed that - removed ties and use 2 small screws (EZ mod BTW)

Few more outings later on a real heavy pedal in some swift current it felt like the drive had weeds on it. Pulled drive and saw sprocket guards rubbing the spine. I figured I could just adjust the placement of the guards - until I discovered the worn out sprockets.




No, the sprocket shaft is fairly new. The original shaft was 5-6 years old but showed a little wear, although it still worked fine with SS sprockets. Replaced it earlier this year.

I'm bummed because I really, really liked the solid feel and smooth performance of the V2 sprockets w/ turbos. I was going to order more V2 sprockets and V2 turbo shafts to do the other drives.

Now I do pedal quite a bit - even when sailing; but at this wear rate I will burn thru a pair of spockets a month.

I mail order my parts from BackYard Boats Hobie dealer as local dealers are kinda far away - which is where these V2 sprockets came from.

BTW I have never used standard plastic sprockets - prefering the SSteel, but I understand the construction material should be similar.

Yak, take a look at the shaft bearing surface inside the sprockets. If they look pocked or cratered, I would guess they are defective. If they are smooth, I don't know what would be causing it unless the vendor substituted the wrong plastic on the batch. Obviously nothing has been overtightened.

I've never heard of this situation happening before with the plastic sprockets, so naturally (with your luck) it would happen to you right away! Wish I could be more help. Perhaps Hobie might be interested in looking at these sprockets? Maybe Matt has some insight on this.

When I bought the Sprocket Shaft, it was not perfect. There was some minor pitting on the surface in one spot. The pitting had no adverse affect on the Stainless Steel sprockets and bushing setup for over 8 months or so of use. My 6 year old original sprocket shaft showed wear and scoring - which is why I got the replacement shaft.

I could probable still use the "near new" sprocket shaft and go back to the SSteel sprocket setup.

If I hear you saying that the plastic sprockets are far less tolerant of sprocket shaft imperfections, or less tolerant of poor lubrication or dirt then they sound less durable.

I'm no slouch when it comes to mainenance, adjustment, repairs & mods. But removing and greasing the plastic sprockets after every 3rd outing would be no joy. At $18.95 a pop, sprocket shafts are not cheap. I'm thrilled my original one lasted 6+ years in the SSteel setup. Again no joy if I have to spring for a shaft 3 or 4 times a year to make the plastic sprockets work.

I try not to cheap-out and have spent enough on drive parts & fins over the years to almost buy a couple new drives

Was my sprocket shaft defective when it arrived "new" - yes indeed if one is expecting a surface like a crankshaft bearing.

So, how long are the Sprocket Shafts warrantied for?
Or the V2 sprockets?

Hard to imagine minor pitting wearing the V2's so quickly. ~30 hours of use

Maybe a soft batch of plastic; which actually did happen to me a long time ago with a pair of 1 month new drives and the older plastic sprocket guards.

Will have to break down the drive - and see. Without new parts in hand, may have to put back the old SSteel.

I was referring to the inside bearing surface of the sprockets themselves, not the shaft. I doubt that the shaft would cause this unless its surface was like sandpaper. It sounds like this shaft was used for a short time with the SS sprockets with no ill effects or degredation to your older bushings?

Once you disassemble it, there may be more clues as to what is going on.

Before assembly. I carefully inspected inside bearing surfaces of both sprockets and gingerly removed the burr/flake that was a remnant of the hole/threads drilled for the guard screws. Insides all looked smooth enough to me. I even slid the sprockets onto the clean dry shaft to test for fit and play prior to any assembly. Was impressed with how well they fit, no play and no binding. Used clean marine grade grease on the shaft and coated the inside the sprocket bearing surface.

Yes the new shaft did not wear out the SS sprocket bushings in 8 months use - and that with an even tighter cable setting.

To see the V2 converted drive go from A1 perfect to sloppy in so short of time is a head scratcher. Reviewed all my steps and can't see anything done wrong. Must disassemble next.

Was absolutely sold on the V2 - loved the drive response & smootheness.

Thanks for all your feedback

Warranty on the drive is now 2 years.

There could be a plastic issue. Would be nice to see your worn ones here. We can send you a few at No Charge so we can look at what your have.

email to info (at) hobiecat.com or contact your dealer for a warranty set.

The only other time we have seen accellerated wear like that is in very gritty water. A guy toured the Mississippi via Hobie Mirage Kayak. His drive wore down in the stainless parts!

_________________
Matt Miller
Former - Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA
(Retired 11/7/2022)

Since your sprockets have had so much wear, especially in the front, it follows that your shaft will also be worn, though certainly to a lesser degree. In automotive work, when one bearing surface is replaced, its opposite is usually machined or resurfaced to original specs. I would recommend the same here. Since your shaft has been used for some time previously with the older bushings it will definitely have some wear by now. Using the exiting shaft surface with your new sprockets will automatically accelerate the wear on the new set as they seat-in to any existing shaft wear, especially in the front portions of each sprocket.

If Hobie doesn't send you a new shaft to go with the new sprockets, you can flip and rotate your old shaft, as noted above (if you haven't already done it), to present a factory fresh bearing surface for your new sprockets. In this first pic, you can see that after just a few months, scoring occurs on the shaft, though in this case, there has been no significant wear. The second pic shows what the opposite side looks like -- fresh as a baby's bottom. Although I continued with the same sprockets, I did reverse the shaft anyway.




Though seemingly unlikely, there is a remote possibility that the small amount of prior wear on your shaft with your older style bushings may have presented enough of an uneven surface to initiate the uneven wear pattern that your new sprockets. Again, I'm not suggesting this as probably, but only in the interest of eliminating any unique or extraneous possibilities that may have applied here. With a fresh shaft surface, this possibility would be eliminated.

Well thank you Matt & Roadrunner!



Well the drive is 6+ years old but the replacement Sprocket Shaft is 8+ months old and V2 sprockets are ~1 month old.

I bet no one hates unexplained mysteries more than Hobie when it comes to trouble-shooting thier products.

Perhaps this pitted Sprocket shaft is the culprit.



This is a close up of one area, there is pitting all along the shaft. The area with the most pitting created the most wear. To be clear, both plastic sprockets are worn but the worst sprocket wear happened on the side with the most pitting. Makes sense.

OK this shaft didn't seem to bother my SSteel sprocket & bushing setup - at least after almost a year of use. But, obviously V2 sprockets need to be (& should be) treated to a nice smooth surface. And, I'm trying, once and for all, to eliminate SS and use the V2s - got 2 more drives after this one to update, I hope.

If the pitted sprocket shaft had been a crankshaft I would have sent it to the machine shop for turning.

Is this a defective Sprocket shaft?
I didn't think this happened to Stainless Steel?

I have 3 Sprocket Shafts that are 6-7 years old and they are scored but none pitted at all.

In hindsight, I probable never should have accepted a pitted Sprocket Shaft as a new one from the dealer - but it was mail ordered. If I had gone to a local dealer that carried an inventory I would have made him pick another one out of the bin

Considering all the data I guess I need 2 new V2 sprockets and a new sprocket shaft.

My aim is not to complain but to provide feedback for Hobie and heads up for Hobie owners.

Lesson learned is if your updating/rebuilding your drive with new sprockets, get a new Shaft & a good one.

Rock On

Matt & Roadrunner

I am pretty convinced now that there had been some bad batches of Sprocket shafts.

I have before me 5 Sprocket Shafts - 3 are from older 6-7 year old drives. These 3 are worn but show no pitting. In addition those original 3 are very shiny & silvery in color. And THEY ARE NOT MAGNETIC. A very powerful magnet does not stick to those original Sprocket Shafts.

Now I have 2 replacment Sprocket Shafts, both purchased from BackYard Boats almost a year ago. One of them is pictured as pitted in my last post. One of them is brand new - never used. These 2 are dull in color not shiny, in fact the surface on even the new one has very tiny pitting along the entire surface - as if it was never finished properly. And THEY ARE VERY MAGNETIC.

These are 2 definitely different batches of metal. I have no faith in the 2nd new Sprocket Shaft as a replacment for the pitted ones. Since it was bought at the same time and likely from the same batch.

Again, not trying to beat up on Hobie - but I will need to get some correctly made Sprocket Shafts, and hopefully be able to return these 2.



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From what I have been reading It looks like part of your problem may be partially caused by electrolytic Corrosion. Take 2 dissimilar metals ie Brass, stainless(high nickel content steel). aluminum, you name it and add a little salt water as an electrolyte and you can get pitting from the salt being broken down into weak acid and pitting can start. Most lubricants and heavier oils/grease tend to be good insulators and sealants against salt water . More lubrication on a regular basis should help a lot. Those pits shown have very sharp edges and machined out the plastic parts pronto and any shaft that looked like that , in my opinion shouldn't have been used with the new plastic bearing surfaces. if it had been highly polished steel, Stainless or carbon, and properly lubricated it wouldn't have shown any wear for a long time.
I use WD40--"Water displacement formula 40"javascript:emoticon(':P') for drying my moving parts as it penetrates well and works as a good solvent but I've found that it doesn't have enough body or staying power for me, as it dries out after a few hours, and doesn't seem to leave a lubricating film. Ive been using "Remoil" or 3n1 pretty successfully.
Polished stainless shafts and the non metallic sprockets should last a very long time. Hopefully someone is listening. Id rather pay a few bucks more for the Quality than go through the hassle you seem to be going through Because some corporate numb nut wants to save a couple of bucks on his bottom line. Last I looked there is an awfull lot of competition for the kayak business and I can buy several of the other guys boats for what I paid for either my outfitter or my adventure.
Hobies are expensive and I expect a lot of bang for my Buck.

The shaft and sprockets have always been bushed with plastic. There is not a metal to metal connection here. Current Sprockets are plastic.

Certainly we are listening. We have asked for the pitted shaft for inspection and are replacing the parts.

Remember though... this is a 6 year old shaft. Not sure we are going to determine exactly where the vendor went wrong after 6-7+ years since we likely purchased the part here.

_________________
Matt Miller
Former - Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA
(Retired 11/7/2022)

No worries Bbuchorn. What you say is true about my folly for using a pitted shaft, however electrolytic corrosion has never been an issue on any of my drives for the previous 6 years. In any case Matt & Hobie have me all taken care of - they always do.




Actually my 3 shiny, non-magnetic 6+ year original shafts were never an issue - they are scored/worn, but not pitted. I happily bought new parts to replace them. The 2 8mo. old replacement(& magnetic) shafts are what has come into question. They are obviously stainless steel - as they don't rust, but even the unused one, when looked at closely, has a very unfinished look & what is best described as "micro pitting".

I know this has been an exhaustive thread to follow. I'm pretty sure there is nothing wrong with the V2 sprockets and that my new sprocket shafts are the culprit.

Hobie's commitment to quality and constant vigilance should reassure any present or would-be Hobie owner.

I once got a brand new sprocket shaft that was very ragged and looked unfinished.