Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[princec]

So, I ordered the belt and pulleys for a DSR/X and had them fitted* to my SR/F, replacing its flimsy crappy 20mm belt with the 25mm one on the DSR/X, for the princely sum of about £150 in labour (estimated - I had it done at the same time as having my tyres replaced).

So the good news is, it Just Werks^TM - trivial fit.

Initial impressions are ... well, it feels basically exactly the same despite the gearing being very slightly different - but as it pissed down when I went to collec the bike and I'm on brand new tyres I didn't exactly test the acceleration.

What is different is that it's a lot quieter than before. And the other, intangible benefit, is I now actually feel confident I'll get home even if I yank that throttle wide open in Sport mode over a bump.

Belt and pulleys ordered from EEMC (UK) - super helpful people.

Cas

* I ain't a mechanic and I've not got a garage let alone half the tools I need.

[mdjak1]

Are these the parts you ordered?  I picked them off the parts lists I have downloaded.

30-08326 Motor Sprocket 22T
30-08476 Rear Wheel Sprocket Mudport. (2023 DSRX)
30-08478 Rear Wheel Sprocket Mudport. (2024 & 2025 DSRX)
30-08325 151T 11MM Pitch 25MM Wide Belt

Not sure why the 2023 rear sprocket has a different part number than the 2024 and 2025 (or if they are interchangeable).  The number of teeth of the rear sprocket isn't mentioned in the parts lists.

Also, do you have the tooth counts on your old sprockets versus the new sprockets?  I'm curious to know the difference.

[eglatzer]

Zero Homepage (Technical Specifications/DRIVETRAIN) says all rear sprocket have 90 teeth.
Motor sprocket for SR/F and SR/S has 20 teeth.

[princec]

I'll go and count them at lunchtime.

I think the speedo is now reading 10% under (formerly about 5% over) - need to find a radar trap to ride past and check on the way home tonight. Acceleration is correspondingly somewhat nerfed, but not badly enough to really notice or care - it feels remarkably like the DSR/X I test rode for a couple of hours now. It's still blisteringly fast in sport mode.

Cas

[princec]

Hm ok it's a bit difficult to count the teeth in situ

According to this post https://www.facebook.com/groups/zmcowners/posts/this-evening-i-installed-the-dsrx-transmission-on-my-srs-and-it-workseverything-/7742029812532826/ (which is the post that inspired me to do it myself in the first place):

"Before, at 50 km/h on the cruise control I was at 47 km/h on the GPS. Now I'm at 51 km/h GPS.  Personally it suits me perfectly." ... which would be about 2% under-reading vs 6.5% over-reading, which is an ~8.5% change in gearing more or less (and thus 8.5% less thrust). I bet due to the approximations here we're actually looking at either a 10% change in gearing which would match if the front sprocket was 22 teeth vs original 20 teeth, or a 5% change in gearing corresponding to 21 teeth.

I would like to twiddle the firmware if possible to change the speedo reading back to over-reading as it's less mentally taxing.

Cas

[Biff]

The Zero DS has a 20 tooth motor sprocket for the 25mm wide belt. https://zeromotorcycles.com/model/zero-ds (it's listed under the technical specifications, drivetrain section) That sprocket would give you the same speed / wheel torque as the stock 20tooth sprocket on the SR/S, SR/F and S.  One advantage of using the 22Tooth motor sprocket (found on the DSR and DSR/X) is that it will make the belt system slightly more robust, as it provides more teeth engagement, and larger radius which reduces the forces in the belt during shock loading of the belt (which can occur when the wheel hops over bumps while accelerating hard). The disadvantage of using the 22Tooth sprocket occurs if you accelerate aggressively often. The larger front sprocket reduces your wheel torque causing you to require more motor torque for the same acceleration, or the same motor torque for longer while getting up to speed. That will contribute to increased motor heating, so you might find your motor running a bit hotter running the 22Tooth sprocket compared to at 20Tooth sprocket, especially if you do frequent aggressive accelerations.

[princec]

I do but then I slow right down again pretty quickly. It doesn't really get hot enough here in the UK for the motor or battery to ever get more than a bit warm.

Cas

[mdjak1]

I've not found the acceleration on my DSR/X to be wanting.   

This sounds like a very good modification for any SR/S or SR/F owner that has snapped a belt or who lives in fear of snapping a belt.   And if they want to maintain the 90/20T gearing, they can purchase the 2024/2025 DS 20T front sprocket rather than the DSR, DSR/X from 22T sprocket.

It begs the question, why doesn't Zero put the larger belt on the street models?

[princec]

It seems to me to be a simple no-brainer modification that they should have started doing 2 years ago.
I've snapped 3 belts in 20,000 miles now, completely negating any fuel price advantage I might have had by going electric. This sucks! But my bike's got enough subtle little mods* now to make it into quite a decent machine now, and I think I have some more mods on the way - custom seat & mesh cover, and then possibly, suspension overhaul, and if I suddenly become rich, forged wheels.

I've decided that I'm going to keep the bike till it becomes uneconomical to repair - probably when one of the major electrical components breaks. I hope that's not for at least another 50,000 miles.

Cas

* SR/S footpegs, Pro-bolt 1" bar risers, MRA Touring screen & spoiler, 12kW charging, and now the belt

[Specter]

why fix simple things, when they can put them on next years model, jack the price a few hundred and sell you a new bike? The bigger better new and improved bike, you can have it for what you paid for last one + $1200 for the 20 dollar fix, hurry,  come to your dealer today!!

Aaron

[princec]

Update with useful anecdotes:

Since upgrading the belt, I've had no less than two stones jam themselves in the belt teeth! Both stones eventually flew out within a few hundred yards - on both occasions I wasn't in a safe position to actually stop and get it out. The takeaway from this is maybe not what you think:

firstly - the belt appears to be undamaged, despite having a stone big enough to get stuck in the teeth in it going round the pulleys

secondly - this never happened once on the old crap thin belt. And it has dawned on me that it is probably because those belts snap immediately when a stone gets in them.

Even so ... I could do with some sort of metal belt guards being fashioned. I'd pay £250 for belt guards.

Cas

[Specter]

just because the belts may look undamaged does not mean they aren't.  the new synthetic belts do not show damage much at all, they just snap, unlike older belts which you get plenty of indications of wear and damage.  it could have stressed and snapped some inner fibres .. or whatever you want to call them and you won't know.  keep an eye on it.

aaron

[princec]

As they've broken without warning every other time, whether I'm accelerating or not, or on a smooth road or not (actually, roads were always smooth), I'm just treating it the same as ever and giving it full send in sport whenever it takes my fancy 1000 miles so far. Let's see if it lasts another 20000.

Cas