In the test, the Bulls Grinder 3: If you want to get into racing bike life today, the best way to do it is with a gravel bike. The all-rounders make the choice of route flexible and have left "old habits" behind. With the Grinder 3, Bulls shows how it's done.
If road bike novices today ask which road bike they should buy, the only advice the experts can give is: don't buy a road bike - buy a gravel bike. All too often you see beginners wandering uncertainly over the slippery main roads and wish them a little more freedom in the routing. Asphalt farm roads or dirt roads, for example, on which you can escape the fast car traffic, are hardly ridable for beginners with narrow racing bike tires. But if you roll along with a voluminous, easy-running tire, even bad routes lose their terror and the cycling fun can really start.
Bulls Grinder 3 - the definition of a gravel bike
If you don't know exactly what a gravel bike actually is, just imagine a cross-country bike with a comfortable seat geometry - meaning a long head tube and short top tube. There are also details such as a gear ratio suitable for climbing and a wide drop handlebar; All kinds of threaded eyelets, with which the gravel bike can be converted into a touring or everyday bike, should not be missing. Disc brakes are a must, weight is less important. First and foremost, the bike has to be stable, so an aluminum frame set is the first choice. Also typical are the tires, which are very wide compared to cross bikes and very, very wide compared to racing bikes – 40 mm are not unusual. Of course, the framework must be adapted to this.
Geometry Bulls Grinder 3
49cm | 52cm | 55cm | 58cm | 61cm | |
seat tube (in mm) | 490 | 520 | 550 | 580 | 610 |
Top tube horizontal (in mm) | 536 | 552 | 569 | 587 | 604 |
head tube (in mm) | 135 | 160 | 189 | 213 | 240 |
chainstay (in mm) | 430 | 430 | 430 | 430 | 430 |
Wheelbase (in mm) | 1020 | 1024 | 1037 | 1047 | 1061 |
Steering angle (in °) | 70 | 71 | 71.5 | 72 | 72 |
Seat angle (in °) | 73.5 | 73.3 | 73 | 72.8 | 72.5 |
Reach (mm) | 370 | 375 | 381 | 389 | 395 |
Stacks (in mm) | 562 | 589 | 614 | 638 | 664 |
One bike that fits this pattern perfectly is the Bulls Grinder 3 – you can see that from the shape of the frame with the very short seat tube. When the seat post is pulled out to the middle, the saddle and handlebars are roughly at the same height; so you sit quite upright, but not exactly short. With a head tube length of 213 mm, the top tube is almost 59 cm long, which means that the 58 Grinder corresponds almost exactly to a size 62 road bike. Even with the smaller frame heights, the ratio of top and head tube lengths is balanced, so that the only special geometric features of the grinder are the short seat tube and the striking sloping shape.
frame | aluminum 7005 |
suspension fork | Carbon |
Wheels | WTB rims, Formula hubs |
Tubes | Schwalbe G-One Performance |
derailleur | Shimano Ultegra |
Gear levers | Shimano Ultegra |
Crank | Shimano Ultegra |
Front derailleur | Shimano Ultegra |
Brake | Shimano BR-R805 |
Seat post | Bull's aluminum |
Saddle | STYX Seta S1 |
Stem | Bull's aluminum |
Links | Bull's aluminum |
Bulls Grinder 3 - complete with Shimano Ultegra
In any case, the test driver sat quite upright on the Velomotion grinder, but that didn't detract from the driving pleasure. It quickly becomes clear that this bike is extremely sporty to drive: the solid aluminum frame is pleasantly stiff, the steering agile. There may be differences to the "real" racing bike and cyclocross bike, but they are not so pronounced that they would give the Bulls Grinder 3 a sluggish character.
The grinder's aluminum frame has a number of appealing details: the flattened top tube looks elegant and is practical when the bike is carried cross-country. The brake line and shifter cables are routed through the down tube, and the bottom bracket housing is kept to the modern PressFit standard. As mentioned, there are also various threaded inserts, for example on the bridge behind the bottom bracket, but also on the fork and rear triangle. Only the top tube lacks a mounting solution for a small frame bag, which is currently very popular in long-distance circles.
Bulls has given the grinder a complete Shimano Ultegra including beautifully designed hydraulic shift-brake handles. As usual, the group works perfectly and is particularly pleasing due to the adapted translation with a 46/36 chainset. Add to that a cassette with 11-32 teeth, and you are just as well equipped for downhill runs as for steep climbs.
Bulls Grinder 3 - the wheels are a highlight
Bulls did a good job when it came to choosing the wheels. What is currently perhaps the most interesting tire on the market, the Schwalbe G-One, was installed here in the expensive tubeless version. The tire rolls extremely easily on asphalt, even with very low tire pressure. We filled the G-One with just over 2 bar, which, with a width of 40 mm, proved to be completely resistant to punctures, even over hill and dale. When the ground is dry, the tire can take on forest soil as well as sandy slopes and bridle paths covered with deep grit. In combination with the low pressure, the grip of the small round profile knobs is enormous.
The WTB rims on the Bulls are also designed for tubeless tires; so the conversion is not a problem. The omission of tubes reduces the rolling resistance even further and minimizes the risk of punctures - a good thing in view of the complicated front wheel removal on the Bulls Grinder 3. A thru-axle is used, which has to be screwed in and loosened with a lot of force, whereby the clamping lever, which tends to slip, does not is just helpful. In view of this difficulty, one would wish for a classic clamping axle, as installed on the rear wheel.
But that's the only negative thing about the Bulls Grinder 3. Even its weight - 10,1 kilos for the test bike - is not noticeable given the brisk handling characteristics. This feature doesn't count for much on a gravel bike anyway; the price, on the other hand, is very relevant. And that is relatively low at 1.899 euros. Which will make racing bike beginners particularly happy, as the Bulls Grinder 3 is a bike that can do much more than just roll quickly over smooth asphalt - but it can do it very well too.
Vincent says
Excellent review, says it all. Good mix of facts and opinion also, the reviewer clearly know what he is talking about. compliments! This gravel bike seems to be real good value for not too much money. With the specs at that price point (Ultegra group, tubeless-ready rims, up to 40mm tires) this offer is very hard to beat. 10+ kilo is a bit on the heavy side though, but OK, for under €2K you can't have it all, can you? I just may have found myself my new all-round all-road race bike 🙂 Thank you!
Nimoy says
The statement "When the seat post is pulled out to the middle, the saddle and handlebars are roughly at the same height; so you sit quite upright, but not exactly short. With a head tube length of 213 mm, the top tube is almost 59 cm long, which means that the 58 grinder pretty much corresponds to a size 62 racing bike," I can't understand. Apart from the fact that "upright" and "not exactly short" are not possible at the same time in my opinion, the top tube length alone is not enough to judge how "long" a bike is, or how "stretched" (i.e. little upright) you sit on the bike. Fortunately, manufacturers now specify reach and stack for a reasonable first comparison of frame geometries. Since the seating position should be independent of the frame geometry compared to the bottom bracket (you know that: plumb from the knee to the pedal...), the saddle has to be moved further towards the head tube with a smaller seat tube angle and thus longer top tube. Incidentally, the Gravel Grinder has a much more "comfortable" geometry than road bikes usually have. Whether the frame has a sloping top tube or not is irrelevant for assessing the peculiarities of the geometry.
Jurgen Beilharz says
Hello ladies and gentlemen
I've also owned a Bulls Gravel Grindel 2017 since Dec. 3. I read your review.
Following question; I got flat tires 430 times within almost 3 kilometers,
Of course I also rode forest and gravel roads. Do you also have the any in
brought experience? Ride with air pressure of 3,5 atmospheres. Can you give me some information about that?
I have nothing but good things to say about the thru-axle on the front wheel, because I always have flat tires
got on the way, I had some car that just stopped driving me home.
I always had to remove the front wheel to do this, without any problems.
The subsequent assembly and fastening of the rigging wasn't much of a hassle either
easy to deal with.
These have been my experiences so far.
I would be grateful for a short info.
Regards
J. Beilharz