[Closed] Rigid fork advice please (1st post)

What type of riding are you planning?

Was the Genesis Tarn out of budget? Its only a couple of quid more and IMHO would be a much better bike (depending on the question above)

https://www.biketart.com/bikes-c1/mountain-bikes-c34/genesis-tarn-10-2017-p21138

those forks are two very different lenghts

if your genisis is a 29er with suspension then it wont be a 445 fork you need , thats a rigid fork to replace a 26 inch 80mm fork or a 29er that has been designed around not having suspension such as ragley td-1

the karate monkey fork is around 470mm and is normal for an 80mm corrected rigid fork.

if you really want a steel fork then you wont do bad there but also look at carboncycles rigids for a much lighter option.

I think the 445 figure was for suspension-corrected 26'' forks. Looking at Salsa's Enabler and Cromoto Grande, both corrected for 80mm, they have a 468mm ACD (both available for around 100€ on bike24).

I had a Cromoto at some point, it was very well finished and quite springy.

l.e. beaten to it

The karate monkey fork is the one you want.

Whilst as you say a rigid fork has advantages over a cheap suspension fork for XC, its an expensive 'upgrade' post purchase.

If I were you I'd ride the genesis as is until something breaks, and invest the £100 in tools and stuff to keep it going. At some point you will fancy an upgrade/change, at that point you can either just buy an off the shelf rigid bike, or you might want something different and end up converting the Core into a rigid single speed.

My current (well, my last 5 really) MTBs have been rigid, it can be difficult and requires a whole different set of skills to riding a FS bike* but can be very rewarding when you're having a good day and the bike just skips about underneath you.

*equally jumping on an FS bike then takes a lot of re-learning too.

Hello Tom, welcome.

The forks will need to fit your frame, your wheel axle, and your brakes. Secondly the geometry should be suitable (wheel size, rake, and length as measured axle to crown).

From the spec sheet listed for the Genesis Core 10, we don't know if the forks have a tapered steerer or not. The frame has a 44mm headtube, so it is likely that it has tapered forks, but not guaranteed. Do you have the bike or can look at one to check?

The spec sheet does not say what spacing the front wheel axle is. A 10mm axle, 100 over-locknut dimension used to be standard, but the 'boost' standard has become very popular, and muddied the water a bit. I expect the Core will have a 10x100 QR axle, but again, it would be worth checking.

The brakes in the pictures of this bike are post mount - I hope they are correct and match the bike.

Both forks that you have linked to have a straight 1 1/8" steerer. This will work with a headset for 1 1/8" straight steerer forks. For a headset for tapered fork it will need an adapter spacer for the lower race.

Both forks you have linked to are for 10x100 QR axle.

Both forks you have linked to have an IS brake mount. This would need an adapter for post mount. There are different adapters required depending on the size of the brake disc on the front wheel. It looks like a 160mm disc in the photos, but please check.

A 120mm travel fork has an axle-crown dimension of about 506mm (looking as a Rock Shox spec sheet, but that'll be close enough). Taking off an allowance for suspension sag (30% of 120mm ~40mm) suggests that a rigid fork with an a-c dimension of about 465mm will be ok. The rake for both forks is similar and will be fine.

I like Surly bikes stuff, so I too prefer those forks.

So, in conclusion:

Check the current suspension forks, because you may need an adapter for the headset.

You will need an adapter for the front brake, but check the size of the disc.

And the axle looks ok, but have a check.

Nothign to add except a hat tip for the00's long, friendly and useful post.

Hi Guys,

Thanks so much for the quick responses. I'll try get back to everyones comments.

@Trailwagger - It is mostly an errand bike in London (hence wanting a lighter rigid) but always enjoyed a bike that I can take offroad when I want to, not anything crazy though. Yes Tarn was out of budget, I got the core for £400.

@Trail_rat Thanks for the link to carboncycles. I've had a look there but a lot of their longer forks are order from USA only. Also Im trying to keep the costs down as much as possible. I can get the Surly fork for £80 although I am considering it now:  https://www.carboncycles.cc/?p=197

@otsdr Thanks. Would that make a difference if the stock forks have 120mm of travel?

@Thisisnotaspoon Yeah I get the expense part. I was thinking I would flog the unused suspension fork on ebay for £50 to cover most of the costs. I probably dont use my current/ new mountain bikes to their full potential. I saw what I thought was a good deal on a bike and thought a small adjustment would make it more suited to my riding. Mostly errands but some forest tracks etc out of London.

@the00 Thanks! I think its not tapered as the suspension fork currently in the bike has a straight steerer tube. Yes I understand about the mounts. My Local Evans said I could bring the bike and new fork in to be changed for about £20 so I'd let them deal with the brake adapter but I am aware it is necessary. I think I might give the Surly fork a shot!

@honourablegeorge Thanks!

Good to go then. Glad we could help. Good luck with it, sounds fun.

@the00 Alternatively I've found a second hand Krampus fork 483mm axle to crown I might take a punt at for £30. Would the extra length give me any issues?

I really appreciate your help.

The Krampus fork is 20mm longer, which will lift the front end of the bike a bit compared to the 'sagged' position of the suspension fork.

If you want to see what difference that will make, just ride around with your suspension fork locked out - the dimension is similar.

If you were using the bike offroad, then I'd be tempted to say that it would be kind of ok. The steering would be a bit slower, because of a slightly slacker head angle and increased trail. But if you are on the road I think you would be better off sticking with a 465mm fork, or something v close.

That doesn't mean that you couldn't find one for sale second hand though. Singular swift forks are 470mm, and would be worth looking out for. Maybe try the classifieds or a wanted ad.

@tom57

id buy the surly fork. Even if you never use it, it'll fetch a silly price on eBay (think of doubling your money at the very least and getting paid to post it!)

ive got a krampus myself and appreciate the extra height on the front end...less weight on my wrists.

You may find this useful...

adventures?

This is a good size for that from rack, above.

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F391895387121

Hopefully, you won’t need to ditch the excellent krampus fork.

Posted 2 months ago | Go to post REPLY | REPORT
greatbeardedone

Member
Reply to: What rigid mtb with panniers for adventures?

These will fit on your krampus fork, though you may need to shim them with some inner tube to avoid scratches.

http://www.chainreactioncycles.com/mobile/dmr-hinged-clamp/rp-prod745?gs=1&sku=sku4902UK&pgrid=55375185827&ptaid=pla-431660306635&utm_source=google&utm_term=&utm_campaign=PLA+All+Products&utm_medium=base&utm_content=mkwid%7Cs1vwX8Mir_dm%7Cpcrid%7C253998738371%7Cpkw%7C%7Cpmt%7C%7Cprd%7C4902UK

then you can fit one of these.

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F33199761601

.at the front of this rack there’s an m4 sized hole on which you can attach a GoPro mount and fit the light of your choice . Mind the nyloc nut and locking washers..

https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F112698500319

advertisement