Raleigh Motus Grand Tour

[saudidave]

Hi All

I've now got a Raleigh Motus Grand tour ebike (2019 model). I chose the 8 speed Nexus hub version as I figured it would be less maintenance and have longer lasting chains than a derailleur. No sales people pointed out the rate of chain wear on an ebike with a central motor and my low maintenance theory is out of the window as I'm adjusting chain tension regularly which is a complete P.I.T.A.

Raleigh have clearly recognised this issue as the 2020 model with hub gear has a tensioner fitted. It won't fit my bike because the frame is drastically different to accommodate the tensioner mount. I have sourced a brand new Shimano Alfine tensioner for £16.00 but that replaces the anti turn washer and the angle of the axle flats to the drop out locators is different than on my configuration.

Question: If I saw off the drop out locators on the rear of the Alfine tensioner and replace the right hand anti turn washer with the tensioner (retaining the L.H.S. anti turn washer), am I likely to have issues? I can't see it myself but if anyone has tried this fix would they please comment?

I've also posted this in the ebike section

Thanks, Dave

[Bonefishblues]

Picture might help, perhaps?

[Brucey]

….Question: If I saw off the drop out locators on the rear of the Alfine tensioner and replace the right hand anti turn washer with the tensioner (retaining the L.H.S. anti turn washer), am I likely to have issues? I can't see it myself .....

In a nutshell; this is a not a good idea, don't do it.

In detail; the Nexus 8 needs two No Turn Washers (NTWs) with one human being stomping on the pedals. You have potentially about double the torque so the NTWs will see a much high stress than normal. What you are proposing is to remove one NTW completely, so potentially the stress on the remaining NTW is four times what it sees in a normal bike and so is the torsional stress in the axle. Axles sometimes break anyway in high torque applications, they don't need any help.

There are two alfine tensioners



CT-S500 is a twin-pulley sprung tensioner that is designed to attach to a derailleur gear hanger. Adjustment of chain tension is automatic.
CT-S510 is a single pulley fixed tensioner that is designed to replace the RH NTW on a frame with vertical dropouts. Adjustment of chain tension is manual.




In the photo above you can see the lump that gives the NTW function.

I daresay you could make a revised bracket for either tensioner type by cutting/welding some pieces together. If you are after least hassle, you should fit a spring-loaded tensioner. Probably you could get a significant benefit by using a better quality chain and using a better quality chain lubricant, too.
FWIW torque is what kills gearboxes and the current shimano arrangement, using a motor drive through the hub gear, tends to cause problems in the hub gear anyway; heavily used systems of this type see quite a lot of IGH failures within the two-year warranty period.

cheers

[saudidave]

Picture might help, perhaps?

Thanks for the response but what do you want a picture of?

The bike is currently not modified in any way and a sprung Alfine tensioner can't be attached as it fixes to a derailleur hanger and my model hasn't got one.I can't attach the other Alfine tensioner as that is intended for vertical drop outs and the none turn locator in to the drop outs is at a different angle to mine.

The drop outs on my bike are the forward facing sliders (open end to the front) that are as common as muck.

Incidentally there is a design issue here because the Shimano technical manual says that the Nexus 8 speed hub with disc brakes isn't compatible with the drop outs. I've emailed Raleigh asking what they propose to do about it

[Bonefishblues]

Being able to see what you are describing helps some people, but I see Brucey has given input in the meantime, so nothing to add from me.

[saudidave]

….Question: If I saw off the drop out locators on the rear of the Alfine tensioner and replace the right hand anti turn washer with the tensioner (retaining the L.H.S. anti turn washer), am I likely to have issues? I can't see it myself .....

In a nutshell; this is a not a good idea, don't do it.

In detail; the Nexus 8 needs two No Turn Washers (NTWs) with one human being stomping on the pedals. You have potentially about double the torque so the NTWs will see a much high stress than normal. What you are proposing is to remove one NTW completely, so potentially the stress on the remaining NTW is four times what it sees in a normal bike and so is the torsional stress in the axle. Axles sometimes break anyway in high torque applications, they don't need any help.

There are two alfine tensioners



CT-S500 is a twin-pulley sprung tensioner that is designed to attach to a derailleur gear hanger. Adjustment of chain tension is automatic.
CT-S510 is a single pulley fixed tensioner that is designed to replace the RH NTW on a frame with vertical dropouts. Adjustment of chain tension is manual.




In the photo above you can see the lump that gives the NTW function.

I daresay you could make a revised bracket for either tensioner type by cutting/welding some pieces together. If you are after least hassle, you should fit a spring-loaded tensioner. Probably you could get a significant benefit by using a better quality chain and using a better quality chain lubricant, too.
FWIW torque is what kills gearboxes and the current shimano arrangement, using a motor drive through the hub gear, tends to cause problems in the hub gear anyway; heavily used systems of this type see quite a lot of IGH failures within the two-year warranty period.

cheers

Thanks Brucey. The current chain is the original one and is due for replacement. It's done 1000 miles and a 0.75 gauge will start to drop in soon. I use finish line dry lubricant and meticulously clean the chain regularly (every 100 miles or so, more if it rains) with a proprietary cleaning bath with brushes prior to relubricating it on the inside of the rollers.

Can you suggest a replacement brand of chain please?

[PH]

The current chain is the original one and is due for replacement. It's done 1000 miles and a 0.75 gauge will start to drop in soon. I use finish line dry lubricant and meticulously clean the chain regularly (every 100 miles or so, more if it rains) with a proprietary cleaning bath with brushes prior to relubricating it on the inside of the rollers.

There's always the possibility that Raleigh fitted a pretty poor chain to start with, it's not one of those things that sell bikes!
On a non assist hub geared bike, I'm currently running a KMC chain intended for one. I'm not as meticulous as you with the cleaning and I don't do any measuring, the other components are cheap enough to replace/reverse when needed. usually that's at about 4,000 miles but this chain has done at least half as much again and is now due for changing. I think it was about £25.

[Brucey]

KMC e1 chain is what is recommended for that type of drive if 3/32" chain in in use.

Dry lube won't do any good at all if it fails to penetrate to the bushings, and it may just not be a good enough lube for the sort of loads that an e-bike puts upon the chain anyway. If you are going to clean the chain every 100 miles then you are better off using a wet lube for sure.

FWIW new chains come impregnated with grease and this usually protects the chain bushings for several hundred miles. If you do clean the chain it is best if you put something as good back in the bushings.

cheers

[PH]

KMC e1 chain is what is recommended for that type of drive if 3/32" chain in in use.
cheers

That's the one I have, though I see it's also available in an EPT version which is apparently some form of rust protection. Something worthwhile?

[Brucey]

…. I see it's also available in an EPT version which is apparently some form of rust protection. Something worthwhile?

dunno; I have not compared an EPT chain with a non-EPT chain.

cheers

[saudidave]

…. I see it's also available in an EPT version which is apparently some form of rust protection. Something worthwhile?

dunno; I have not compared an EPT chain with a non-EPT chain.

cheers

I have come up with two alternative strategies to install a gear hanger

1) Many years ago when I was a small boy (55 yrs ago when I was 11,to be exact) I used to walk miles to the LBS to look at the 5 gear sports bikes I coveted. Back then many of them had Benelux derailleurs attached to a hanger conversion plate that was secured to the drop out via the mudguard stay mount threaded hole. I’ve sourced one of those on eBay for a couple of quid and i’ll See if I can modify it to accommodate the anti turn washer. If I can I will attach the shimano alfine spring tensioner to that.

2) The second alternative is to get the Raleigh tensioner
Fixed to the 2020 model and make a conversion plate to fix it to the chainstay via two unused slots obviously intended for some otherwise unknown accessory on what is probably a standard frame sourced from Taiwan or the like.

There is always a way, you just have to find it. I’d appreciate any suggestions as to my proposals

Dave

[Brucey]

I'm also sure there is 'a way' and I'm glad that you seem willing to get stuck in.

I have not examined the dropouts in your machine in detail but if there are unused holes I reckon that might be the easiest way to mount a special bracket, with the caveat that if the tensioner gets a knock, you don't want the bracket to be so robust that parts of the frame start getting knocked off. Some options;

1) I've made gear hanger brackets by using a M10x1 threaded nut of the correct width and adding a 'tab' feature for the mech/tensioner ( a weld build -up and some grinding), then welding the nut to a bracket. [ Thin M10x 1 nuts are found on quick-release type rear wheel axles; since these break with monotonous regularity in cheap bikes most LBS scrap bins are infested with them.]

2) The CT-S510 tensioner uses a modified NTW that appears to be pressed into position. It may be possible to remake the insert and make the CT-S510 bracket/tensioner work for you.

3) It may be possible to weld to a NTW and make a combined NTW/bracket that fits your bike.

The old-style gear hangers that used to come with rear mechs BITD will spare you some work; if you can weld one to an NTW that might be favourite.

cheers

[saudidave]

This is what I have. The slots on the chainstay should provide a fixing medium if a hanger plate won’t work

[saudidave]

I haven't updated this due to a flooded house (!), however I now have a solution:

I studied the latest model Motus grand tour in a couple of bike shops, scoured ebay for an old school hanger accessory like they had on 70's 5 gear sports bikes and then after not too much searching ebay again I found what appears to be the same, or a very similar tensioner to that which Raleigh have fitted to the modified 2020 model.

I can bolt the tensioner to the inside of the right hand chainstay quite easily with two bolts utilising the existing slots, after filing it a bit so that the curved top edge is flat and it doesn't look "stuck on" I can then bolt the tensioner to that and it should, in theory work in exactly the same way as the 2020 modification that Raleigh have adopted. I've reversed the NT washers as well now to give some further room for wheel adjustment so I'll touch up the damaged paint whilst I'm at it. I can't see any reason at all why this shouldn't work perfectly when adjusted properly so that the chain runs perfectly in line. I don't think it will be necessary, but if it does a washer to shim out one side of the hanger should sort that.

As I previously stated, there is always a way, you just have to find it

Dave

This is what Raleigh have fitted to this years model

This is what I have

[saudidave]

Hi all

I finally got around to fitting the tensioner to one of the slots on the chainstay and after fixing a washer in between the chainstay and hanger at the front bolt position, to act as a shim and get the jockey wheel exactly parallel to the chain, all is running quietly and smoothly. The tensioner is working well. I haven't put the chain retention loop back on yet until I've undertaken extensive testing.

There is always a way, you just have to find it!

Dave