Newbie with stealthy e-bike

[Tinkerer]

Hi all. Newbie here with a standard cross bike but with a few modifications! I'm running a Vivax Assist motor inside the seat tube with the battery in the saddle bag. I've not wished to broadcast this expensive system for a number of reasons so I've changed to a Topeak saddlebag and hidden the control button inside an out front computer mount. There is cabling between the two but no casual observers seem to ever notice it.
It's a lightweight system of under 2kgs so doesn't unduly affect the characteristics of the bike. It provides a nice little boost (circa 150W at the road) rather than monster power.
Further customisation to the bike includes bottle bosses in the seat stays to resolve a manufacturing error of missing rack eyelets (if only I'd noticed before I got the motor fitted!) and a homemade quick release full length mudguard system. I can whip both 'guards on or off in around 30s!
I also dug out some old racing aero wheels and had them rebuilt onto MTB hubs. The bike flies (even without the motor!) with these beauties in! I can actually stop properly with carbon rims for the first time ever, owing to the disc brakes of course.
I've had to upgrade one or two other bits and pieces but it's really a finished project now.
Never thought I'd own an e-bike but my bad back got me looking for a little assistance.

 

[D8ve]

Love the bike. Stealthy and a good bike in first place. Cool

 

[jazper53]

Maybe able to hide its electric credentials, but not its quality, which could make it very desirable to those Lycra clad Villains.

 

[Tinkerer]

Maybe able to hide its electric credentials, but not its quality, which could make it very desirable to those Lycra clad Villains.

Well I'm lycra clad but would make a very poor villain lol. When not riding it, my bike is either securely stored at home or work (we have very good facilities at work) so that's not the chief reason for the stealth. Let's just say it's not a fully 'authorised' expense at home I also have a reputation as a fast rider and I suppose people will think I'm a fraud if they find out I have an e-bike! All my advertised fast rides are completely genuine but it would get boring to have to explain that all the time. But it's nice to be able to tell the forum about this bike at last as I think it's pretty cool.
I ride around 120 miles per week commuting to and from work and, as this is a cross bike, I can use a variety of routes on or off road (depending which wheels I run). The mudguard system means the bike is great in the rain and I have also fitted a rack and trailer to it for load lugging. It's still plenty quick when stripped back so I do have a nice versatile bike.
It took me ages to find the right model of frame that had 31.6 mm seat tube (most cross bikes are 27.2mm) with the geometry I wanted and with disc brakes so my choice was basically narrowed down to just this. Luckily it's a smart enough bike.
I would like to upgrade to TRP HY/RD disc brakes, not so much for more power/better modulation but mainly as they auto-centre. This would help wheel changes. But the BB5s are great brakes so I'm in no rush.

 

[103Alex1]

Inspiring. .

 

[EddiePJ]

Now that has really got me thinking.

Very nice.

Did you source the components from a UK supplier?

 

[Tinkerer]

Now that has really got me thinking.

Very nice.

Did you source the components from a UK supplier?

Yes. I got the standard bike from a LBS. I had to move the stock FSA chainset to another bike and get a Shimano (Ultegra in my case) Hollowtech II. I then had to send the bike to Steve @ electric mountain bikes, electric bicycle, electric bike kits, folding bicycles to get the motor and kit fitted. Unfortunately, and despite using a bike box, my rear mech took a clobbering so that has had an upgrade to Ultegra too (found one for just £30!).
Two mates, experienced racing cyclists, have ridden the bike. One knew in advanced about the motor, the other didn't....despite handling the bike before our ride. My mate and I had a little bit of childish fun attacking the other after swapping bikes a couple of times before I let me other mate have a go. He still didn't realise it had a motor as he rode my bike along but I leaned over and switched it on and it wasn't long before he was attacking us. So it's definitely stealthy.
I've since converted my carbon wheels and now the bike is nice and fast without even enabling the motor. I rode into work this morning and managed a 20mph ride (over 15 miles) without the motor running or trying too hard, so the extra 2kgs definitely doesn't noticeably affect the bike.
There are some downsides though. It's an eye wateringly expensive system and so are the spares (i.e. the battery). The motor also needs an annual service so I'm going to have to get it back to Steve each year. It's also only a nice boost and doesn't give monster power (although very efficient for such a lightweight system). Is it worth it? Honestly, for me, probably not as my bad back has improved this year and I'm already a strong rider. But it is cool!

 

[103Alex1]

There are some downsides though. It's an eye wateringly expensive system and so are the spares (i.e. the battery). The motor also needs an annual service so I'm going to have to get it back to Steve each year. It's also only a nice boost and doesn't give monster power (although very efficient for such a lightweight system). Is it worth it? Honestly, for me, probably not as my bad back has improved this year and I'm already a strong rider. But it is cool!

Do you know roughly what the annual servicing costs are likely to be ? Not seen that mentioned before.

How much does it really help on long steep hills in terms of easing the climb effort (say a 1 mile 17% climb for example) ? That's the key thing for me over extra speed really. If it were 1,000 Euros less than it is I'd seriously consider it alongside getting a nice fast bike, but it's so much more for seemingly so little additional power 'on paper' it's hard to make the value equation add up !

Think it's perhaps most compelling if you ride in groups / pairs where you're looking to keep up with others who are stronger riders, so opening up more options and levelling things out. If I could check in a nice converted bike like that with me on a plane for a few days of impulsive riding in Mallorca now and again in the Spring & Autumn I'd be extremely tempted to somehow make the numbers work, but the problem of not being able to take your battery along has kind of killed that idea at the moment !

 

[Tinkerer]

Do you know roughly what the annual servicing costs are likely to be ? Not seen that mentioned before.

How much does it really help on long steep hills in terms of easing the climb effort (say a 1 mile 17% climb for example) ? That's the key thing for me over extra speed really. If it were 1,000 Euros less than it is I'd seriously consider it alongside getting a nice fast bike, but it's so much more for seemingly so little additional power 'on paper' it's hard to make the value equation add up !

Think it's perhaps most compelling if you ride in groups / pairs where you're looking to keep up with others who are stronger riders, so opening up more options and levelling things out. If I could check in a nice converted bike like that with me on a plane for a few days of impulsive riding in Mallorca now and again in the Spring & Autumn I'd be extremely tempted to somehow make the numbers work, but the problem of not being able to take your battery along has kind of killed that idea at the moment !

I don't have anything like as steep as that to ride up on my commute but for sure it will help quite a lot. The system is giving you around 75W/kg, which is huge (an elite athlete can max out around 6.5W/kg) so you will notice the benefit up steep climbs for sure.

I did a little test this week on Strava comparing normal road bike vs Vivax bike over the same segment in near identical conditions up a 2.5 miles drag (around 1.5% average) and my av. was virtually 4mph quicker on the Vivax bike for slightly less effort. That was nearly 1 min quicker, which is an awful lot over that short distance. I mark all my 'assisted' rides as private, by the way, so I don't upset the leaderboards (I'd have smashed the KOM with that time!). I know you are less interested in that type of riding but it gives you an idea and would certainly help you keep pace with stronger riders. You'd be struggling to get more than around 75 mins of juice out of the standard battery, by the way. That's fine for my commuting but you would have to use it sparingly if riding all day. Which is why it's good that it rides so well when switched off.

Oh, another thing is you lose the use of the bottle cage on the seat tube. There are inexpensive clip-on solutions if this is a problem which work OK (I've got one on another bike).

I've read through the manual and it just says to check with your airline operator before taking the battery on a flight. So, it's doesn't sound completely unfeasible. It would need removing from the bike and be well wrapped and strapped inside a bike box, I'd have thought.

Oh, nearly forgot - I cannot remember what the servicing costs are. Not much I don't think; £20-£30 rings a bell. But you would have to send the whole bike if you didn't feel confident in removing the motor yourself (I understand it's not too difficult if you have the correct tool and instructions).