[{"data":1,"prerenderedAt":398},["ShallowReactive",2],{"article-en-common-problems":3,"articles-en":301},{"id":4,"title":5,"applies_to":6,"author":8,"body":9,"confidence":277,"description":278,"extension":279,"faq":280,"meta":287,"navigation":288,"path":289,"seo":290,"sources":291,"stem":296,"test_bike":297,"topic":298,"updated":299,"__hash__":300},"content_en\u002Fen\u002Fwissen\u002Fcommon-problems.md","Common Problems After an E-Bike Conversion",[7],"all","fabio-gentsch",{"type":10,"value":11,"toc":263},"minimark",[12,16,21,121,124,127,136,139,147,150,153,172,179,182,185,197,200,203,210,213,227,230,239,243,250,256,260],[13,14,15],"p",{},"Most problems after a conversion come as no surprise: axle, spokes, connectors, sensor, chain. Here is what typically causes them and what you can do. Most points are experience, not officially verified.",[17,18,20],"h2",{"id":19},"overview","Overview",[22,23,24,40],"table",{},[25,26,27],"thead",{},[28,29,30,34,37],"tr",{},[31,32,33],"th",{},"Problem",[31,35,36],{},"Cause",[31,38,39],{},"Fix",[41,42,43,55,66,77,88,99,110],"tbody",{},[28,44,45,49,52],{},[46,47,48],"td",{},"Axle spins in the dropout",[46,50,51],{},"No torque arm",[46,53,54],{},"Fit an arm, tighten nuts to torque",[28,56,57,60,63],{},[46,58,59],{},"Spokes break",[46,61,62],{},"Thin spokes, motor weight",[46,64,65],{},"Stronger spokes, re-tension after 100 km",[28,67,68,71,74],{},[46,69,70],{},"Motor cuts out",[46,72,73],{},"Water in a connector",[46,75,76],{},"Clean, grease, seal",[28,78,79,82,85],{},[46,80,81],{},"Jerky when pulling away",[46,83,84],{},"Cadence sensor",[46,86,87],{},"Check sensor gap and settings",[28,89,90,93,96],{},[46,91,92],{},"Chain wears quickly",[46,94,95],{},"Mid-drive, shifting under load",[46,97,98],{},"Ease off when shifting",[28,100,101,104,107],{},[46,102,103],{},"Range too low",[46,105,106],{},"Ideal figures, cold",[46,108,109],{},"Calculate realistically",[28,111,112,115,118],{},[46,113,114],{},"Workshop refuses",[46,116,117],{},"Counts as a manufacturer modification",[46,119,120],{},"Find a conversion-friendly workshop",[13,122,123],{},"Now line by line.",[17,125,48],{"id":126},"axle-spins-in-the-dropout",[13,128,129,130,135],{},"This is the most dangerous case. A hub motor produces torque at the axle. Without a torque arm, the flattened axle can turn in the dropout and, in the worst case, work its way out. The wheel can come loose, and that does not happen quietly. With aluminium dropouts and front motors an arm is always right. Details under ",[131,132,134],"a",{"href":133},"\u002Fen\u002Fknowledge\u002Ftorque-arm","torque arm",". Tighten the axle nuts with a torque wrench and check them after the first rides.",[17,137,59],{"id":138},"spokes-break",[13,140,141,142,146],{},"The motor makes the wheel heavier, and the spokes have to transmit more force. Thin spokes often do not last long under that. Stronger spokes are better. Re-tension the spokes after about 100 km, because freshly built wheels settle. A wheel that was already weak before is no exception. If you are replacing wear parts anyway, think of the wheels, see ",[131,143,145],{"href":144},"\u002Fen\u002Fknowledge\u002Fframe-and-weight","frame and weight",".",[17,148,70],{"id":149},"motor-cuts-out",[13,151,152],{},"This likes to happen in rain, especially at the connectors. Water in a connector causes contact resistance or a short. The connectors (Higo, Julet) are the most common source of faults in the whole kit. Proceed like this:",[154,155,156,160,163,166,169],"ol",{},[157,158,159],"li",{},"Disconnect the connector and let it dry.",[157,161,162],{},"Clean the contacts, for example with contact spray.",[157,164,165],{},"Rub in a little grease so that no water gets in.",[157,167,168],{},"Route the cable so that water does not collect near the connector. A small drip loop helps.",[157,170,171],{},"Secure it neatly with spiral sleeving and cable ties so nothing chafes.",[13,173,174,175,146],{},"More on the components in the ",[131,176,178],{"href":177},"\u002Fen\u002Fknowledge\u002Fglossary","glossary",[17,180,81],{"id":181},"jerky-when-pulling-away",[13,183,184],{},"With a cadence sensor, assist feels more like being pushed. That comes with the design and is not a defect. Check:",[186,187,188,191,194],"ul",{},[157,189,190],{},"The gap between sensor disc and sensor, usually only a few millimetres",[157,192,193],{},"Settings in the display or controller, such as the start-up level",[157,195,196],{},"Whether the sensor works cleanly with the magnet",[13,198,199],{},"If you do not like the jerkiness, look at a kit with a torque sensor, even though it costs more.",[17,201,92],{"id":202},"chain-wears-quickly",[13,204,205,206,146],{},"This mainly affects mid-drives. The chain carries the motor's force too, and shifting under load adds to the strain. Ease off briefly when shifting and keep pedalling lightly. Check the chain regularly and replace it before it takes the cassette and chainring with it. More on comparing the types under ",[131,207,209],{"href":208},"\u002Fen\u002Fknowledge\u002Fmid-drive-vs-hub-motor","mid-drive vs hub motor",[17,211,103],{"id":212},"range-too-low",[13,214,215,216,222,223,146],{},"Manufacturer figures are mostly ideal values; in practice often only about 70 % counts (",[131,217,221],{"href":218,"rel":219},"https:\u002F\u002Fwww.giga.de\u002Ftech\u002Fwer-billig-kauft-kauft-zweimal-diese-fehler-solltet-ihr-vermeiden-wenn-ihr-eurer-fahrrad-zum-e-bike-umbaut--01K0YYJEVGW05AE9TTBCPW0DAM",[220],"nofollow","GIGA","). Cold, headwind, terrain and weight subtract more. Plan with the lower end of the range and use realistic values in the range calculator. Details under ",[131,224,226],{"href":225},"\u002Fen\u002Fknowledge\u002Fbattery","battery",[17,228,114],{"id":229},"workshop-refuses",[13,231,232,233,238],{},"Some workshops will not service or repair converted bikes because the conversion counts as a modification of the manufacturer's product (",[131,234,237],{"href":235,"rel":236},"https:\u002F\u002Ffahrrad-xxl.at\u002Fblog\u002Fe-bike-umbausatz",[220],"Fahrrad XXL","). Ask before converting whether your workshop will stay on board. If not, find one that takes converted bikes. That saves frustration when something jams later.",[17,240,242],{"id":241},"when-nothing-works-at-all","When nothing works at all",[13,244,245,246,146],{},"If the motor will not start despite connectors, sensor and battery being fine, narrow it down: measure the battery with a multimeter, check the display, unplug connections one by one and reconnect them. If you find no fault, contact the dealer. That is why a dealer in the EU who offers support is worth it. What that means for the budget is under ",[131,247,249],{"href":248},"\u002Fen\u002Fknowledge\u002Fcosts","costs",[13,251,252],{},[131,253,255],{"href":254},"\u002Fen\u002Fconfigurator","Does a conversion fit your bike?",[17,257,259],{"id":258},"how-reliable-is-this","How reliable is this?",[13,261,262],{},"The statements on range and on workshops that refuse conversions come from the linked sources. Causes and fixes for the other problems are experience and assumptions that Fabio is still checking.",{"title":264,"searchDepth":265,"depth":265,"links":266},"",2,[267,268,269,270,271,272,273,274,275,276],{"id":19,"depth":265,"text":20},{"id":126,"depth":265,"text":48},{"id":138,"depth":265,"text":59},{"id":149,"depth":265,"text":70},{"id":181,"depth":265,"text":81},{"id":202,"depth":265,"text":92},{"id":212,"depth":265,"text":103},{"id":229,"depth":265,"text":114},{"id":241,"depth":265,"text":242},{"id":258,"depth":265,"text":259},"assumption","Axle spinning, broken spokes, motor cutting out, jerky starts, fast chain wear: causes and fixes from everyday conversions.","md",[281,284],{"q":282,"a":283},"Why does the axle spin in the dropout?","Usually there is no torque arm or the axle nuts are too loose. Fit the arm and tighten with a torque wrench.",{"q":285,"a":286},"Why does my motor cut out now and then?","Often water in a connector is the cause. Clean it, protect it with grease and seal the connection.",{},true,"\u002Fen\u002Fwissen\u002Fcommon-problems",{"title":5,"description":278},[292,294],{"title":293,"url":218},"GIGA: mistakes when converting to an e-bike",{"title":295,"url":235},"Fahrrad XXL: e-bike conversion kit","en\u002Fwissen\u002Fcommon-problems",null,"haeufige-probleme","2026-11-09","14nWv2Mym_3okvjNVWmZXTxbc4PGOHQkBeGym2kHkcI",[302,308,314,320,322,328,334,340,346,354,361,367,373,380,386,392],{"path":303,"title":304,"description":305,"topic":306,"applies_to":307,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Fbattery","E-Bike Battery for a Conversion: Position, Space, Range","Where the battery fits on a converted bike, how to measure the space, what branded cells bring, real-world range and how to dispose of it.","akku",[7],{"path":309,"title":310,"description":311,"topic":312,"applies_to":313,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Fbrakes","Brakes for an E-Bike Conversion: What You Need","Rim or disc, cut-off levers and sensors: which brakes are enough for a 250 W pedelec and when an upgrade is needed.","bremsen",[7],{"path":315,"title":316,"description":317,"topic":318,"applies_to":319,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Fcoaster-brake","Coaster Brake and E-Bike Conversion: What Works","A coaster brake is the most common deal-breaker. Which motors work, where coaster-brake variants exist and when to leave it.","ruecktrittbremse",[7],{"path":289,"title":5,"description":278,"topic":298,"applies_to":321,"confidence":277,"updated":299,"author":8},[7],{"path":323,"title":324,"description":325,"topic":326,"applies_to":327,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Fconvert-bike-to-ebike","Convert a Bike to an E-Bike: Overview and Steps","What a conversion costs, which motor fits, what the law says and when you should buy a used e-bike instead. An honest overview from the workshop.","fahrrad-zum-e-bike-umbauen",[7],{"path":329,"title":330,"description":331,"topic":332,"applies_to":333,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Fcosts","What Does an E-Bike Conversion Really Cost?","Cost items at a glance: kit EUR 400 to 1,700, brakes, tools, small parts. Plus the comparison with used and new (about EUR 2,500) and the cost calculator.","kosten",[7],{"path":335,"title":336,"description":337,"topic":338,"applies_to":339,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Fframe-and-weight","Frame and Weight: Which Bike Suits a Conversion","Steel and aluminium are usually fine, carbon is not. Plus the magnet test, total weight, warranty and the wear parts to replace before converting.","rahmen-und-gewicht",[7],{"path":341,"title":342,"description":343,"topic":344,"applies_to":345,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Fglossary","E-Bike Conversion Glossary: Terms Explained","Rated power, volts, watt-hours, newton metres, PAS, torque sensor, Higo and Julet, controller and display: the glossary for e-bike conversions.","begriffe",[7],{"path":347,"title":348,"description":349,"topic":350,"applies_to":351,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Fhub-spacing","Hub Spacing and Axles for an E-Bike Conversion","How to measure hub spacing, quick release versus thru-axle, spreading 130 to 135 mm on steel frames and what to watch with dropouts.","einbaubreite",[352,353],"front","rear",{"path":355,"title":356,"description":357,"topic":358,"applies_to":359,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Fmeasure-bottom-bracket","Measure Your Bottom Bracket for a Mid-Drive","How to measure shell width and bore of your bottom bracket and tell BSA 68\u002F73, Pressfit and BB30 apart. Step by step for a mid-drive motor.","tretlager-messen",[360],"mid",{"path":362,"title":363,"description":364,"topic":365,"applies_to":366,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Fmid-drive-vs-hub-motor","Mid-Drive or Hub Motor: What Suits You?","Ride feel, hills, gears, installation and cost compared, with a clear guide to when a mid-drive and when a front or rear hub motor makes sense.","mittelmotor-oder-nabenmotor",[360,352,353],{"path":368,"title":369,"description":370,"topic":371,"applies_to":372,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Fmotor-types","E-Bike Conversion Motor Types Compared","Front, rear and mid-drive motors, friction rollers and seat-tube motors compared: feel, installation, cost and which bikes suit which.","motorarten",[7],{"path":374,"title":375,"description":376,"topic":377,"applies_to":378,"confidence":379,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Fpedelec-law","Pedelec Law: 250 W, 25 km\u002Fh and Walking Assist","What a conversion may do legally: 250 W rated power, assist only while pedalling up to 25 km\u002Fh, walking assist up to 6 km\u002Fh and what lies beyond.","pedelec-recht",[7],"source",{"path":381,"title":382,"description":383,"topic":384,"applies_to":385,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Ftools","Tools for an E-Bike Conversion: The List","Which tools you need for front, rear and mid-drive conversions and what kits usually lack, above all the lockring tool.","werkzeug",[7],{"path":387,"title":388,"description":389,"topic":390,"applies_to":391,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Ftorque-arm","Torque Arm: When You Need One","Why the axle of a hub motor turns in the dropout, when you need a torque arm and how to fit it.","drehmomentstuetze",[352,353],{"path":393,"title":394,"description":395,"topic":396,"applies_to":397,"confidence":277,"updated":299,"author":8},"\u002Fen\u002Fwissen\u002Fwheel-sizes","Wheel Sizes and ETRTO for E-Bike Conversions","Inches are unreliable, ETRTO is not: how to read wheel size off the tyre and avoid the 635\u002F622 and 406\u002F451 traps.","laufradgroessen",[352,353],1794254701701]