converting to non suspension front forks

[Andrew Brown]

I have a Cyclotricity revolver and it has the standard suspension fork. I think it would be better and maybe a bit lighter too with a non suspension fork and would be easier to get on and off for me as it really does make the bike oddly taller. . Does anyone have any suggestions as to whether converting to a normal fork would be costly in parts and labour. The from wheel is the motor wheel whether this means a stronger fork is needed I font know. Any info most appreciated

 

[Bikes4two]

• I looked into doing this some years ago for an old MTB someone had given me and which I wanted to use as a 'shopping bike'
• It is as you say, the front forks are heavy and totally unnecessary for ordinary bike riding IMHO
• After a bit of research I quickly realised that to replace the suspension forks with non-suspension forks is less than straight forward and with an elecric motor in the front wheel, motor driving torque is an additional factor too. (this article HERE gives you some idea as to the complexities involved).
• It might be the case that Cyclotricity can supply a 'bespoke' replacement for you but in any case I suspect it might be a relatively costly process which ever way you go, but TBH, that's just my guess.
• In my case it was easier to buy (a used) non-suspension frame and swap across all the bits, but I suspect that's not a viable option if the frame you have is suitable apart from the forks.

 

[Benjahmin]

Some years ago I looked into doing the reverse, putting suspension forks onto a non suspension frame.
Geometry quickly became the main issue. The at rest length of a suspension fork is longer that a standard one and frame geometry is designed to account for this.
So, if you swap your forks, I suspect that the whole framr will 'tip' forward, throwing your weight onto the bars. What this would do to the handling is unknown.
You have an electric bike. Why are you bothered about weight? That's what the motor is for.
My bike (avatar) is around 28-30kg as I carry two batteries, yet it gets me around the hills of Wales.

 

[Bonzo Banana]

There may be some variations in that model but a quick look online shows a small geared hub motor in the front fitted to very low end suspension forks. Some rigid steel forks would be stronger and lighter. Looks to be a threaded fork with a quill stem. Disc forks tend to go for more money than forks with V mounts but if you have mechanical disc brakes you could consider fitting V brakes to the front if it will save money overall.

I would measure the forks and see how long the replacement needs to be. Also what is the outside diameter of the forks to make sure you get the right size. Then I would probably keep looking on ebay for some cheap forks that match the specification you need.

If you buy secondhand and play the waiting game for the right product you shouldn't have to pay a lot. I've bought forks for 99p plus postage ending up as about £7 delivered and that included a quill stem and the headset but those were V based forks.

 

[Nealh]

If I were changing to a fixed fork with a front hub then it would have to be a decent chromoly fork, a good fork is about £120/130. So something like a nice surly disc trucker or one of their various they make, If the hub is only 250w rated then one doesn't need to use torque arms.

 

[Bonzo Banana]

If I were changing to a fixed fork with a front hub then it would have to be a decent chromoly fork, a good fork is about £120/130. So something like a nice surly disc trucker or one of their various they make, If the hub is only 250w rated then one doesn't need to use torque arms.

While a chromoly fork would be nice I don't think it has to be, there is nothing wrong with high tensile steel forks and can be stronger with stronger dropouts. Before the advent of CF forks most entry level road bikes had high tensile steel forks without issue and those cheap entry level rigid mountain bikes never have problems with failing forks. Also sometimes chromoly forks can be a little more focused on weight saving and can be weaker. Many of the older chromoly steel frames have failed because they corroded on the thin sections of the butted tubes making them unsafe. You just don't have the same issue on plain gauge high tensile steel frames. A lot of chromoly steel frames have high tensile steel parts like the stays and the Brompton for example has a mixture of different steel metals used in the frame to give different properties at different points and because its brazed there is no issue with mixing such steels. I think the forks are high tensile steel from what I recall. I think high tensile steel gets a bad press but most of the bikes in the world use high tensile steel, across Africa, Asia, South America etc. Over 95% of all bikes in the world are steel and almost all of those are high tensile/high carbon steels not chromoly steels.

Someone carried 1/2 ton on a Buffalo bike and those are high tensile steel. They are officially rated to take 100kg on the rack alone.

http://www.buffalobicycle.com/why-buffalo

 

[Scorpio]

Discussions in the past say you can expect problems with geometry, suspension forks raise the front of the bike - if you replace with fixed forks the front of the bike will be lower.

I fitted a set of £25 Suntrour suspension forks last year and they're been fine on my town bike, you might find new forks are a big improvement over the ones you have now.
My other bike has nastly old susp forks with lots of wear, it rides ok but new forks would make it a lot nicer!
Lots of choices at https://bankruptbikeparts.co.uk/collections/forks

 

[Bonzo Banana]

Discussions in the past say you can expect problems with geometry, suspension forks raise the front of the bike - if you replace with fixed forks the front of the bike will be lower.

I fitted a set of £25 Suntrour suspension forks last year and they're been fine on my town bike, you might find new forks are a big improvement over the ones you have now.
My other bike has nastly old susp forks with lots of wear, it rides ok but new forks would make it a lot nicer!
Lots of choices at https://bankruptbikeparts.co.uk/collections/forks

Quite a lot of options at that site. I'm certainly not saying its not an issue but hybrid type bikes tend to have short travel suspension forks so geometry is less of an issue. Looking at the bike it looks like its raised with a suspension fork and returns to a level geometry when the fork is compressed. Maybe the same frame is used on a bike with rigid forks. You could always do a mini-mullet where you put a thicker tyre on the front wheel than the rear but to me it looks like that frame is designed for rigid forks and just has suspension forks stuck in there. Once you've adjusted handlebar height which is easy to do with a quill stem and correctly angled the saddle and handlebars it should be fine with rigid forks. Looks like a nice simple ebike with easy to maintain and replace parts. Nothing proprietary, the sort of bike you can customise easily.

 

[Waspy]

Maybe the same frame is used on a bike with rigid forks.

Absolutely, my Giant CRS hybrid bike came in two options when I bought it, rigid or telescopic fork, I doubt very much if they made two completely different frames to suit the forks.

The Woosh Rambletta comes with two fork options but the same frame.

I recently changed my old mountain bike suspension forks with 63mm of travel for a much more modern pair with 100mm of travel. Apparently this 37mm (or 1.5 inch) difference upsets all the geometry, well if it does, I certainly can't tell, if anything the bike feels better.

I guess all this stuff is very important to serious downhill racers but for a green-lane bimbler like me, maybe not so much.

 

[Bonzo Banana]

Absolutely, my Giant CRS hybrid bike came in two options when I bought it, rigid or telescopic fork, I doubt very much if they made two completely different frames to suit the forks.

The Woosh Rambletta comes with two fork options but the same frame.

I recently changed my old mountain bike suspension forks with 63mm of travel for a much more modern pair with 100mm of travel. Apparently this 37mm (or 1.5 inch) difference upsets all the geometry, well if it does, I certainly can't tell, if anything the bike feels better.

I guess all this stuff is very important to serious downhill racers but for a green-lane bimbler like me, maybe not so much.

To be honest that is my experience too but don't like to assume replacing front suspension with rigid forks will be fine as I don't want people to have issues that I have caused but I feel with a bit of common sense you can tell if it will be ok. On a lot of cheaper bikes they just throw on rubbish suspension forks and don't give a damn if you ask me. I've bought many cheap bikes with dire front suspension forks often completely seized when I get them but its been good for me as I have bought them very cheap, sometimes just a few pounds and some cheap rigid forks often transforms them into much safer more usable bikes. Maybe you don't get that as much nowadays as I think you get less elastomers in forks that just degrade into nothing. Collapsing forks is just about the most dangerous thing that can happen when you ride a bike, it face plants you in the road for HGV's and other vehicles to roll over you. For me rigid steel forks are the right choice.