Yep , plan c or d.

Yes, I ground down crank, which worked well for a year. PAS has worn down though and now I'm trying locktite (adhesive) to keep the bolt in place with hopefully the correct pressure on the PAS. There's got to be a better system!

Or you can go at it a bit heath robinson, with a hacksaw and file cut off a bit of the inside edge of the pedal. mines been like this for over a year now and did the job:

[ATTACH type=full" alt="34350]34350[/ATTACH][ATTACH type=full" alt="34351]34351[/ATTACH][ATTACH type=full" alt="34352]34352[/ATTACH][ATTACH type=full" alt="34353]34353[/ATTACH]

Thank you for the photos! Yes I ground down crank for a better fit, which worked for a year only.

Ken when you remove the crank arm (pedal arm if you like ) the axle it sits on is part of the BB (Bottom Bracket) it is basically a shaft with a bearing on each side.

Remove the PAS and refit the crank arm tightly, measure the actual gap left. It should be 1 - 2mm greater then the PAS width.

With the pedal removed look directly in to the side cup and you should see some castellation's/crenulations, the V12L also has similar and these push firmly in to these to grip and prevent the actual PAS outer part rotating, the PAS inner part with small splines grip the BB axle then rotates freely when axle is rotated.

Sometimes the small splines brake off or don't grip the axle to well so if this is the case remove it and wind some black electrical tape or similar on to the axle then refit the PAS to grip better.

With the crank arm back in place there should be free air between the arms inner face and the PAS.

Thank you. This is very helpful.

Unfortunately, changing the bottom bracket will solve one problem, but may give you one or two there issues to resolve!

 

If you are planning to use a longer bottom bracket to give you more space to install the sensor, this will push the front chainrings further away from the bike frame. You will therefore need to consider the chain line between the front chainrings and the rear freewheel cogs. Also, the front derailleur may not have the reach required to shift the chain to the outer ring.

 

I have tried changing the bottom bracket for a longer one in order to fit the PAS and always end up reverting to the original as gear changing becomes compromised.

 

Grinding cranks does the job, but it sounds a bit brutal!

I have tried changing the bottom bracket for a longer one in order to fit the PAS and always end up reverting to the original as gear changing becomes compromised.

if you replace the bottom bracket, in 4 times out of 5 cases, you go from 118mm spindle length to 122mm. The chain ring is moved out by 2mm requiring a simple adjustment for the front derailleur and you gain two new cartridge bearings.

Thank you. This is very helpful.

Thank you. This is very helpful.

Nealh, Thank you, thank you. It seems that, while my PAS worked for a year with no problem, the inner ring (with small spines) was being turned not by the axle, but by contact with the crank. I will need to build up the axle (with tape ?) so the inner ring is turned by the axle. Daaahhh!

 

I appreciate your, and all of the other responses, to my self-imposed dilemma. Thank all y'all.

Nealh, Thank you, thank you. It seems that, while my PAS worked for a year with no problem, the inner ring (with small spines) was being turned not by the axle, but by contact with the crank. I will need to build up the axle (with tape ?) so the inner ring is turned by the axle. Daaahhh!

 

I appreciate your, and all of the other responses, to my self-imposed dilemma. Thank all y'all.

 

This self amalgamating table is great for that purpose, its nice and rubbery and the splines in the PAS seem to grip it better than the normal black elec tape. ( actually my fav type of tape for many diy things as its not sticky but sticks to itself when stretched. - perfect for wrapping round connections for 100% waterproofing ):

https://www.toolstation.com/self-amalgamating-repair-tape/p23876

Nealh, Thank you, thank you. It seems that, while my PAS worked for a year with no problem, the inner ring (with small spines) was being turned not by the axle, but by contact with the crank. I will need to build up the axle (with tape ?) so the inner ring is turned by the axle. Daaahhh!

 

I appreciate your, and all of the other responses, to my self-imposed dilemma. Thank all y'all.

Installed new PAS (V12L - same as first one). Ground down crank more, nice fit, Spines turn with axle... but no peddle assist. I give up.

KT d12L if no ones suggested it... make sure you get the JULET connector read the yosepower kit thread from the beginning and it should answer many of your future questions or problems....

 

I can not find any UK stock and I just used my last one, with all the miles and road muck they only last about a year to 18 months but easy install and work as expected... I would say remove the back of the sensor and pop some poxy or hot melt glue in to waterproof it up a bit or use as is if it's well sealed when/if you get it.

 

ebay (china) Kt d12l

 

aliexpress (China) Kt d12L the seller I purchased off

When I tried to fit the KTV12L to my wife's trike it was apparent there was not enough room on the left hand side, and the 'old fashioned' bottom bracket had no spline holes to catch the sensor housing. In any case the sensor and housing was way too wide, to fit between the pedal and the frame.

 

I went back to yose and they sold me a 2 piece sensor (you can get them a lot cheaper on ebay), but even then it needed a dremmel to make the disk thin enough, hot melt glue to fix it to the pedal and a 3mm shim between the sensor and its supporting bracket, but now works a treat. If it starts causing problems, then I may swap it to the RHS and glue the disk to the chain ring.

 

The centre grip on the sensors is quite flimsy and if the disk sticks for any reason, the rotating crank wears the centre down and it doesn't work anymore, hence the hot melt glue.

 

I suspect that if you have space on the crank, and a bottom bracket that fits the sensor, it is a good solution, otherwise my advice would be to forget the v12L and just get a 2 piece sensor.

Does anyone know of a slim version of the KT-V12L?

slim version

Doubt you'll get much slimmer, on the PAS that is... Any smaller and the costs would increase not to mention mounting it. There is many of styles try Aliexpress and search "PAS" or "KT pedal assist" or "pedal assist sensor". I found the above version to be the best option although a little extra waterproofing or a spare helps. The one I am rocking now is over 2 years old I add some hot-melt-glue to the inside. Normally they last 6 months if soaked.

Doubt you'll get much slimmer, on the PAS that is... Any smaller and the costs would increase not to mention mounting it. There is many of styles try Aliexpress and search "PAS" or "KT pedal assist" or "pedal assist sensor". I found the above version to be the best option although a little extra waterproofing or a spare helps. The one I am rocking now is over 2 years old I add some hot-melt-glue to the inside. Normally they last 6 months if soaked.

 

It exists, but it's hard to order in my area.

It exists, but it's hard to order in my area.

I found them to be inconsistent at best, some did work well but failed not long after, while others are stiff to operate, not mentioning 4 or 6 poles instead of 12 & the fact you'll need to remove the crank arm to install. Aliexpress deliver to most territories. Where do you hail from?

Not a pas sensor expert, but my original yose power kit (about 18 months old) included pas sensor is a nominal few mm thinner in its smallest dimension than a similar type bought via ali express.. circa 1- 2mm maximum difference - nominal..

Any pas sensor will work in all probability and if your crank axle is just a tad wider than 17mm these can be a pita.

afaik its generally the 12x magnet type sensors that give anyone a problem, so replacing a 12x magnet sensor shouldn't be an issue at all.

 

If this design is too wide nothing stopping you from looking at 2 part options with a thinner magnet disk perhaps, A right hand sensor disk could even be epoxied or otherwise fixed to the chainring even..

A right hand sensor

Is there a KT right? Edit long time since I looked topbikekit has a D12R OMG, I have about 2x D12L's do really need another? ten quid shipped Aliexpress -Never had any issues with 12 mag a part from aforementioned water ingress. got the codes mixed up theres D12 or V12 - D12 is what I use. apologies.

Edited January 30, 20251 yr by PC2017

My only reference for 12x magnet sensors having a bad rep is an incidental comment from one of the forum gurus in reply to my update of an initial pas issue with my conversion kit. The solution i ended up with was using a right hand sensor that required a steel plate on which the sensor is mounted be fixed behind the bottom bracket securing nut/ring. a 12x magnet sensor.. ( apparently the 'worst sensor', tho so far so good this end.)

 

btw when looking for e-bike items on the ali-express sales portal and using the bit i want ie 'brake sensor' in the search text, I never seem to get uber cheap offerings.. However if i search for something else 'e-bikey' the item im really after will often appear in the 'also ran' list of goods at a cheaper 'initial'? price.. - often it will be a bogus loss leader, but on occasion a real bargain could be found.. ie try looking for ebike brake sensors and you may get a $2 pas sensor in the 'similar items you might be interested in list?

 

I have no proof but if like me you dont see the ads your sure you overlooked at bargain basement prices when those items are your target it might be worth a 5 minute experiment...

Edited January 30, 20251 yr by thelarkbox

ali-express sales portal

Aye, aliexpress is funny, for xbox series XS parts I trawl through pages before I find the price and seller I am looking for + signed out will offer better prices than signed in. I fear its territory centric. The new "Choice" free shipping has added confusion imo, I picked up a "hailong" adapter mount for cheap but had to purchase 2 other items to complete the sale[ still cheaper than ebay]. Search criteria helps somethings aren't list the way us brits say em!

You inspired me...

 

Things of note for the KT-LCD3 [and possibly other LCD based KT] C1 will need changing from "reverse" or left to "forward" or right. C1 = either 01/02/03.

 

Took me a while to figure; as I was focused on magnet to sensor distance. On the plus side the front chain ring (cog) was steel so a couple of 4mm additional magnets to raise out the 12 pole ring helped although I have not tested this without the added distance. The magnet ring itself needed cutting to sit around the bottom bracket. Looks stealthy as... Which was an idea from my teeth cutting back in 2016, so glad I was able to bring it to fruition many-a-moons later.