Known Issues & Problems with BULLS Products + Help, Solutions & Fixes

The only pre-assist chain break I ever witnessed in ~30 years of MTBing was when a friend's chain broke MILES from our car. He'd neglected his chain severely and it was both rusty and grimy. We re-used a pin and shortened his chain - less than ideal but we made it back to the car...

Someday I'll need to replace my eMTBs' entire drivetrains, and I'll probably go with SRAM's EX1 groupset, an 8-speed arrangement designed for to withstand the extra torque from the likes of Brose (MUCH thicker chain, for one thing). Best price I've found so far on EX1 components is from Niagra Cycle - if anyone's seen them cheaper please let me know!

Only 8 speeds? IMO (and according to E-Mountainbike Magazine), that's plenty for my needs - I feel that 11 or even 10 speeds is overkill, and those use thinner links so there's only so much chain makers can add in terms of strength. As it is, I frequently find myself jumping 2-3 gears at a time with 10- and 11-speed pedal assist - I really don't need the "in-between" gears with the motor's help.

If you (or anyone reading this) splurges (or has splurged) for the KMC X11e Sport or Turbo, I'd be curious to learn how it holds up after 100+ miles of hard offroading. I find that my "regular" x11e and x10e chains start stretching 0.5% at about 100 miles, then to 0.75% at 150+ (which is when I change mine).

For now, I've decided to just buy several of the Silvers (Bulls' OEM) at less than half the price of either Sport or Turbo, and just change them every 150-200 miles. Bike-Discount sells Silvers for less than $30, but the cheapest I've found Sport for was $65 (Turbo $80). If you know a place that sells the for $50-60, I'd probably try it myself...

I just noticed that the x11e available on the German site "bike-discount.de" (linked above) isn't even listed on the US version of KMC's website! The only "Ebike Approved" 11-speed chains they show are the Sport and Turbo, so I guess they want us to spend twice as much unless we're willing to pay for international shipping. The x11e Silver is only shown on KMC's EU site... intetesting.
 
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I just purchased a 2016 Bulls 29er with Brose motor. The problems with my bike is the frequent system power cut Iam getting. The power will cut off for no reason and turn itself back on after 1 or 2 sec later. What could be the problem?
had this happen and it was just dirty connection, remove battery clean contacts and battery and reinstall problem gone
 
The only pre-assist chain break I ever witnessed in ~30 years of MTBing was when a friend's chain broke MILES from our car. He'd neglected his chain severely and it was both rusty and grimy. We re-used a pin and shortened his chain - less than ideal but we made it back to the car...

Someday I'll need to replace my eMTBs' entire drivetrains, and I'll probably go with SRAM's EX1 groupset, an 8-speed arrangement designed for to withstand the extra torque from the likes of Brose (MUCH thicker chain, for one thing). Best price I've found so far on EX1 components is from Niagra Cycle - if anyone's seen them cheaper please let me know!

Only 8 speeds? IMO (and according to E-Mountainbike Magazine), that's plenty for my needs - I feel that 11 or even 10 speeds is overkill, and those use thinner links so there's only so much chain makers can add in terms of strength. As it is, I frequently find myself jumping 2-3 gears at a time with 10- and 11-speed pedal assist - I really don't need the "in-between" gears with the motor's help.

If you (or anyone reading this) splurges (or has splurged) for the KMC X11e Sport or Turbo, I'd be curious to learn how it holds up after 100+ miles of hard offroading. I find that my "regular" x11e and x10e chains start stretching 0.5% at about 100 miles, then to 0.75% at 150+ (which is when I change mine).

For now, I've decided to just buy several of the Silvers (Bulls' OEM) at less than half the price of either Sport or Turbo, and just change them every 150-200 miles. Bike-Discount sells Silvers for less than $30, but the cheapest I've found Sport for was $65 (Turbo $80). If you know a place that sells the for $50-60, I'd probably try it myself...

I just noticed that the x11e available on the German site "bike-discount.de" (linked above) isn't even listed on the US version of KMC's website! The only "Ebike Approved" 11-speed chains they show are the Sport and Turbo, so I guess they want us to spend twice as much unless we're willing to pay for international shipping. The x11e Silver is only shown on KMC's EU site... intetesting.

So you only get 200 miles per chain? Even with an eMtb setup I thought components would go for longer.
 
So you only get 200 miles per chain? Even with an eMtb setup I thought components would go for longer.
Depends on the motor and how hard I ride the bike, but for my Bulls w/Brose and an 11-speed drivetrain, which I ride pretty hard, my chain checker tool shows 0.5% stretch every ~100 miles and 0.75% at ~200. According to modern maintenance guidelines, I'm waiting too long.

Park Tool says, "If you are using a chain designed for ten or fewer gears, replace your chain as it nears the 0.75 percent mark. If you are using an eleven or twelve speed chain, replace your chain once it has reached 0.5 percent wear. For two-sprocket or single speed bikes, replace your chain as it reaches the 1 percent wear mark."

Cheaper chain wear tools (under $10) either show 0.5% and 0.75% OR 0.75% and 1%. I have one of each since I have both 10- and 11-speed ebikes...
 
High praise for KMC!

Update on my chain break posted on Oct 16th. I reported the break to KMC and Bulls.

Focus on good news - High praise for KMC!
KMC immediately supported replacing the chain while noting that it could still be operator error (I can own that!). I jut received the replacement chain yesterday (after returning the broken one to them at their expense) and SURPRISE, they upgraded it to the Turbo chain. WOW! Now that's how a company creates a loyal customer! Nice job KMC. I've got the new chain on with no issues yet. Seems to shift a bit more smoothly with the coating but maybe that's just the happy rider in me talking. To support KMC, I bought a second chain on my dime of the same type. Win - Win for both of us!

Focus on the bad news - no help from Bulls
Bulls reply was quite disappointing - its a wear part and even if it was under warranty I would need to take it up with KMC. I contacted my two local dealers and the reply was the same - wear part, tough luck and oh by the way it's a cheap part so you should just replace it yourself. It's a $60 - $80 part so where I come from that's not cheap! Only helpful response was to reassure me that the overrev of the Brose motor should be a non issue. I hope so!

Overall I remain VERY HAPPY with this bike. It is a beast uphill and has the right balance of components to handle the downhills well. I feel it's only giving me upside from the traditional MTBs I have been riding for years...
 
Fyi you can order emtb chains from bike discount.de in Germany for twenty to thirty bucks... They have a lot of good prices and large selection since ebikes are prevalent over there, a bigger one time order makes shipping reasonable too.
 
Fyi you can order emtb chains from bike discount.de in Germany for twenty to thirty bucks... They have a lot of good prices and large selection since ebikes are prevalent over there, a bigger one time order makes shipping reasonable too.
I spend at least a grand a year on that site, $200+ at a time, but they keep running out of $30 KMC x11e chains ($6o+ in the US). Now I'm trying YBN's version for about the same price. We'll see if it holds up longer than the KMC.

And Cletus, regarding Bulls' vs. KMC's customer service, it's like the old saying goes: the squeaky chain gets the grease, but the wheel maker just wants to make more wheels!
 
What chain line you guys using.
I have 640 miles on mine now and it’s all dirt and steep single track riding.
Have no visible chain wear yet.
But i use Dumonde tech chain lube
 
What chain line you guys using.
I have 640 miles on mine now and it’s all dirt and steep single track riding.
Have no visible chain wear yet.
But i use Dumonde tech chain lube
KMC x11e - I'm not sure what you mean by visible wear, but I go by Park Tool's o.5% stretch recommendation for 11sp chains (most chain checkers only have 0.75 and 1% indicators).
I can't "see" chain stretch without a tool/ruler etc., but would rather replace a few chains proactively than have a stretched chain wear out my chainrings and cassette prematurely...
 
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I use dial calipers. And measuring with them there no visible wear or stretch.
Using calipers i can see if it’s the ID or the OD of the rollers that is wearing.
I have found on both mtb and motocross bikes the Dumonde tech chain lube has added about 50% chain life over most chain lubes. It’s little bit messy but if you put it on little thick and get good penetration into rollers then while external clean with rag it’s not so messy.
But I’m a bit of a clean freak when i comes to my bikes.
That chain has almost 800 miles on it now

That was supposed to be chain lube in my original post
 
Tnt,
Can I ask what helmet you have on the seat. I have been wanting a Full face . That looks like good air flow , just what I need for Texas heat. Thanks
 
Tnt,
Can I ask what helmet you have on the seat. I have been wanting a Full face . That looks like good air flow , just what I need for Texas heat. Thanks
That’s the new bell wrap with the removable face guard.
So far in 102 temps it was good even with face on. Had it about 4 weeks now and i love it. Very comfy great air flow and long hot climbs you can quickly remove face guard and it’s open face
 
Thanks Tnt,
I spoke with Jenson, and my helmet size will be in a month. Salesman said he wears the same one. As to your suspension rebuild. I have had them apart, and if you don't do those regularly can be difficult. I will probably be sending mine to a place near the Tesla Giga factory, in Sparks Nevada. Sorry can't remember their name . Their site sounded pretty good. Quick turn around of your fork. And they do them all the time. I will see if I can find their name tommorow.
 
I was jus
Thanks Tnt,
I spoke with Jenson, and my helmet size will be in a month. Salesman said he wears the same one. As to your suspension rebuild. I have had them apart, and if you don't do those regularly can be difficult. I will probably be sending mine to a place near the Tesla Giga factory, in Sparks Nevada. Sorry can't remember their name . Their site sounded pretty good. Quick turn around of your fork. And they do them all the time. I will see if I can find their name tommorow.
i was just wondering what most people do and if it would be worth my time to offer my suspension knowledge and services.
I have worked with fox development for 20yrs and just recently ventured into Rock Shox and finding there very little difference and same issues with friction and slick grease bushings none oil bath on both forks.
The grease makes no sense for fighting stiction and wear.
So i oil bath all my forks and use a special oil developed by a retired fox engineer that fox tried to copy with there new gold oil. But fox uses a poor quality base stock and it doesn’t work nearly as well.
 
Looks like it is madsuspension.com. Based in Reno Nevada. They rebuild Rockshox and Fox suspensions, with quick turn around.
 
High praise for KMC!

Update on my chain break posted on Oct 16th. I reported the break to KMC and Bulls.

Focus on good news - High praise for KMC!
KMC immediately supported replacing the chain while noting that it could still be operator error (I can own that!). I jut received the replacement chain yesterday (after returning the broken one to them at their expense) and SURPRISE, they upgraded it to the Turbo chain. WOW! Now that's how a company creates a loyal customer! Nice job KMC. I've got the new chain on with no issues yet. Seems to shift a bit more smoothly with the coating but maybe that's just the happy rider in me talking. To support KMC, I bought a second chain on my dime of the same type. Win - Win for both of us!

Focus on the bad news - no help from Bulls
Bulls reply was quite disappointing - its a wear part and even if it was under warranty I would need to take it up with KMC. I contacted my two local dealers and the reply was the same - wear part, tough luck and oh by the way it's a cheap part so you should just replace it yourself. It's a $60 - $80 part so where I come from that's not cheap! Only helpful response was to reassure me that the overrev of the Brose motor should be a non issue. I hope so!

Overall I remain VERY HAPPY with this bike. It is a beast uphill and has the right balance of components to handle the downhills well. I feel it's only giving me upside from the traditional MTBs I have been riding for years...

Btw.....Bulls, in my experience so far, sucks when it comes to standing by their warranty and customer service.
 
I had a display delaminate and Bulls was pretty good about warranty on that, and i was able to get my software updated at the same time.
I have found a lack in dealer support with bulls and i don’t want to drive 2.8hrs one way for warranty work so i finally sold my bulls And went with Fantic.
I have had two warranty issues an both where handled in 1 call and i had tracking number for replacement parts the same day.
Best part was all i needed was to send them photos of the part and i got he replacement.
Living over n hour away from closet bike shop that kind of service works well for me.
I don’t miss my Bulls bike I’m happy they gave me a reason to look at other bikes.
There a great bike but their dealer network and knowledge need improving.
But if you need support i reach out to Andy or Barney. There pretty good about getting back to you or helping you.
 
I had a display delaminate and Bulls was pretty good about warranty on that, and i was able to get my software updated at the same time.
I have found a lack in dealer support with bulls and i don’t want to drive 2.8hrs one way for warranty work so i finally sold my bulls And went with Fantic.
I have had two warranty issues an both where handled in 1 call and i had tracking number for replacement parts the same day.
Best part was all i needed was to send them photos of the part and i got he replacement.
Living over n hour away from closet bike shop that kind of service works well for me.
I don’t miss my Bulls bike I’m happy they gave me a reason to look at other bikes.
There a great bike but their dealer network and knowledge need improving.
But if you need support i reach out to Andy or Barney. There pretty good about getting back to you or helping you.
We get excellent support from the New Zealand agent, Karl Bull (no relation), but I was expecting it to be a bit easier in Europe. I should have new part on Monday, then I'll try to take the old one apart, which is what I was really looking for help with.
 
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