Top Speed

[Road Scholar]

What sort of top speed are you folks seeing. I got an indicated 86 mph the other day before I had to backdown. I was out riding with some friends a few weeks back and they all had big bikes. I thought for a few moments I was pushing 90 but that might have been wishful thinking.

Fletch

 

[wspollack]

What sort of top speed are you folks seeing. I got an indicated 86 mph the other day before I had to backdown. I was out riding with some friends a few weeks back and they all had big bikes. I thought for a few moments I was pushing 90 but that might have been wishful thinking.

Fletch

I started a thread on this last July, shortly after getting my '22 C 400 GT delivered; see:

C 400 GT: Top Speed in Agreement With Owner's Manual

In case anyone was wondering ... The owner's manual for my 2022 C 400 GT lists (on page 197) a top speed of 86 MPH. I recently received footage of that scoot, with post-break-in mileage on it, confirming that figure. The anonymous rider noted that the throttle was held WFO, and that the...

www.bmw-scooters.com

The short answer is:

- 86 on level ground, after the break-in period.

- 89 on level ground, a few thousand miles later.

- 92 (okay, 91.6) on a long downhill run, last Nov., with 4,000+ miles on the scoot.

Readings were made with a GoPro Hero9 Black, which has a sterling GPS chip (18Hz, faster than most GPS devices). The speedometer read a few percent higher (depending on tire wear) for each test.

 

[Road Scholar]

Good to know. The bike handles well at high speed. You don’t want to ride sustained that fast, but nice to know you have all that reserve power for a long uphill. Do you know if the bike has a governor that limits speed, either by hardware or software?

 

[wspollack]

Good to know. The bike handles well at high speed. You don’t want to ride sustained that fast, but nice to know you have all that reserve power for a long uphill. Do you know if the bike has a governor that limits speed, either by hardware or software?

Real answer from me:

Nope, sorry, I don't know, re governor.

Speculation:

It seems to me, from my testing -- especially that last downhill test -- that it just runs out of engine, in terms of HP and RPM capability. It is just a 350cc thumper. But, of course, I could be wrong about that.

 

[Road Scholar]

I agree the bike tops out where the design has its limits. I did some searching and you can buy a chip which re-maps the fuel injection and increases the power and torque. I’m sure you can get and aftermarket exhaust and remap the engine as well. These types of mods will most likely void your warranty and make the bike less reliable. Like you said, it’s a 350 single, fun as hell to ride. I’m more than happy with this bike’s performance. If I want more power I’ll take out the Ducati. Thanks for all the info!

 

[wspollack]

I agree the bike tops out where the design has its limits. I did some searching and you can buy a chip which re-maps the fuel injection and increases the power and torque. I’m sure you can get and aftermarket exhaust and remap the engine as well. These types of mods will most likely void your warranty and make the bike less reliable. Like you said, it’s a 350 single, fun as hell to ride. I’m more than happy with this bike’s performance. If I want more power I’ll take out the Ducati. Thanks for all the info!

All good points.

Well short of the factory warranty's running out, I already paid for the extended BMW warranty -- after just a few month's riding -- before I spent the money on something useful (e.g., wine, women, and song, as they say). I decided early on in my ownership last year that the scoot is definitely a keeper. So, yep, I won't be messing with any of the goodies that could void that.

Like you, the bike is fine for me (and I'm 75 now, so I've got much of the hooliganism out of my system), and fine for the occasional two-up trips. I am pleasantly surprised at how smooth and peppy those 350CCs are, and the handling is just superb: I have yet to grind anything -- sidestand, centerstand, exhaust, etc. -- which is a first for me, on all the bikes I've owned over the last 25 years. And I've been trying. It looks like tomorrow will be the start of the riding season for me, but I have to take it easy for the day, what with two new tires that I had put on last month.

 

[Road Scholar]

Upgrade the rear shocks. Makes a big difference to have rebound dampening adjustment.

 

[wspollack]

Upgrade the rear shocks. Makes a big difference to have rebound dampening adjustment.

Ya know, I'm still thinking about that.

I think the $500 is reasonable -- see https://bikerzbits.com/bmw-c400x-yss-g-top-black-series-tu362-440trcj-01-888a.html -- if those are the shocks you have. But it's the preload changes that have me concerned. My wife rides with me occasionally, and when she does I change the preload from 3 to 5 (and then put them back, for my typical and much more frequent solo day trips).

This change is pretty easy to do with the stock shocks, but with shocks that have threaded adjusters it seems to me to be a more complicated process, what with a lot of turning, and mentally keeping a count of those turns.

@byee has those YSS shocks, and likes them. I jumped in a thread he started about those, and that back-and-forth preload adjustment was on my mind. See https://www.bmw-scooters.com/index.php?threads/yss-rear-suspension-upgrade.2319/ .

 

[Road Scholar]

I bought the Yacugar emulsion shocks. I’m happy with them but they are twice the price of YSS. Not sure whether that’s a value. I may buy another 400 and I would get the YSS’s for the money. Just my opinion.

 

[wspollack]

I bought the Yacugar emulsion shocks. I’m happy with them but they are twice the price of YSS. Not sure whether that’s a value. I may buy another 400 and I would get the YSS’s for the money. Just my opinion.

A couple of questions for you:

1) I don't see them for the C 400 scoots. I'm looking at https://www.yacugar.com/appl-bmw.html . Do you have a link for the specific product?

2) Do they have threaded adjusters? That is, would I have to count turns to switch between solo and two-up preloads, or is there some easy way to alternate between two settings?

Thanks for any help.

 

[XYZMETA]

The max I got was an indicated 92mph on the A3 I believe it was 🤪. I felt I could of got a bit more. Maybe 94mph. But had to slow down. Was really fun.

 

[Hornblower]

Assuming my bike is typical, the speedo reads about 3 mph fast. This was determined by comparison to GPS measured speed. For a single cylinder, 350 cc "thumper", seeing 85-86 on the speedo seems pretty respectable to me, which, of course, is only around 83 mph. If I'm going on a longer trip or want to go faster, I just get out the R1250GS.

 

[wspollack]

The max I got was an indicated 92mph on the A3 I believe it was 🤪. I felt I could of got a bit more. Maybe 94mph. But had to slow down. Was really fun.

Assuming my bike is typical, the speedo reads about 3 mph fast. This was determined by comparison to GPS measured speed. For a single cylinder, 350 cc "thumper", seeing 85-86 on the speedo seems pretty respectable to me, which, of course, is only around 83 mph. If I'm going on a longer trip or want to go faster, I just get out the R1250GS.

The owner's manual (at least on my '22 C 400 GT) states a top speed of 86 mph, so I think we can all agree that the scoot, after break-in, can reach that, or I imagine that there would be all sorts of litigation regarding BMW's printing false information.

You can see in one of the videos in that thread I started -- https://www.bmw-scooters.com/index....p-speed-in-agreement-with-owners-manual.2490/ -- the difference between actual (18Hz GPS) and displayed speed. Here, I'll save anyone curious some trouble, and post it again:

Now, that shows the difference -- display vs. actual -- at the top end of the bike.

I don't know whether that percentage-over holds true throughout the 0-90ish mph range. It had been my experience with both bikes and cars that over-displays like that are percentage-based, anywhere from around 2% - 9%. (This is all perfectly legal, and the OEMs would get sued big-time if they ever displayed a speed lower than actuality, and then the rider or driver got a ticket or had an accident.)

Regarding percentages, I say "had been my experience" because a little over a month ago I bought another 350cc thumper, a Royal Enfield Meteor 350. After break-in service, I did a test to see whether that bike had a percentage over-display of X%, or not.

It turns out, according to my test, that the Meteor does not do percentages, but rather appears to just add about 3 mph at pretty much all speeds, once you get moving. Here's the video I made for that test:

One of these days, I plan to duplicate that sort of test with the scooter.

 

[MAC400GT]

90mph on flat surfaces, got it up to 94mph on a downhill with a little push from the wind, that's with a high flow air filter & Akrapovic Exhaust.

 

[mzflorida]