DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

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mbgjt1   10 W

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DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

Post by mbgjt1 » Nov 09 2020 1:59am

I am looking at getting the 140r moto frame and pairing it with some suspension

Rider weight would be 125 kg, mostly street riding and some fire trails.

What options would you all recommend? It seems the USD -8 is a very popular option. What is the difference between this and the USD-8s?

It looks like the USD-8s is about 150 USD cheaper.

Any advice would be much appreciated!

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MadRhino   100 GW

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Re: DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

Post by MadRhino » Nov 09 2020 3:33am

Personally I don’t like DNM suspension components. They can do the job on the street, but I find them very poor performance in mountain trails. If you don’t have the budget for a good fork, check the adds on pinkbike for a used DH fork, even the older ones. Find a top of the line Marzocchi, Rockshox or Fox. The parts are still available for the old ones that were high end racing forks. Learn to service them and they will last you a very long time, with proper fonction and tuning options.

I prefer spending 400$ and some time to rebuild an old 2000$ racing fork, than buying a 400$ brand new Chinese crap.
Make it fool-proof, and I will make a better fool.

benjamin84   100 W

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Re: DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

Post by benjamin84 » Nov 09 2020 9:32am

The DNM USD forks are fine for firetrails (gravel roads of good quality), and fine for street. Anything like a rocky road, or proper trail riding and they are pretty bad to be honest. Very sharp response over small bumps, little feel. I would avoid them if you can afford something better.

I've been using them on my Q140MD and I like them less and less the harder I'm riding. Did a bit of full throttle forest trail riding today and they are clearly the limiting factor on the bike. The rear DNM shock is actually pretty good though, no real complaints on that from me although I am far from the fastest rider out there :)

mbgjt1   10 W

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Re: DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

Post by mbgjt1 » Nov 12 2020 2:55pm

MadRhino wrote:
Nov 09 2020 3:33am
Personally I don’t like DNM suspension components. They can do the job on the street, but I find them very poor performance in mountain trails. If you don’t have the budget for a good fork, check the adds on pinkbike for a used DH fork, even the older ones. Find a top of the line Marzocchi, Rockshox or Fox. The parts are still available for the old ones that were high end racing forks. Learn to service them and they will last you a very long time, with proper fonction and tuning options.

I prefer spending 400$ and some time to rebuild an old 2000$ racing fork, than buying a 400$ brand new Chinese crap.
Hi mate,

Thank you for your reply, I have had a look at some really nice 2000 $ racing forks on FaceBook marketplace that people are trying to get rid of.. however, they are still quite expensive (at around 1k or so). I will choose this option and go for a higher quality fork and spend some money on refurbishing / servicing it.. Can't beat the price of the USD - 8 though!

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MadRhino   100 GW

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Re: DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

Post by MadRhino » Nov 12 2020 4:07pm

Wait for the snow. They come cheap off season. I buy most frames and components in the winter.
Make it fool-proof, and I will make a better fool.

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MadRhino   100 GW

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Re: DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

Post by MadRhino » Nov 12 2020 4:50pm

Sorry I had believed that you are on the same hemisphere as I

We are end of season here, and it is easy to forget that some are living where the riding season is about to begin, and others have warm weather al year long.
Make it fool-proof, and I will make a better fool.

mbgjt1   10 W

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Re: DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

Post by mbgjt1 » Nov 14 2020 7:57pm

benjamin84 wrote:
Nov 09 2020 9:32am
The DNM USD forks are fine for firetrails (gravel roads of good quality), and fine for street. Anything like a rocky road, or proper trail riding and they are pretty bad to be honest. Very sharp response over small bumps, little feel. I would avoid them if you can afford something better.

I've been using them on my Q140MD and I like them less and less the harder I'm riding. Did a bit of full throttle forest trail riding today and they are clearly the limiting factor on the bike. The rear DNM shock is actually pretty good though, no real complaints on that from me although I am far from the fastest rider out there :)
What are you planning to change them to? Yes they are very reasonably priced but if they are limiting your trail rides then it might pay to consider other options. Are you using the DNM RCP-2 on the rear?

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Re: DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

Post by mbgjt1 » Nov 14 2020 7:58pm

MadRhino wrote:
Nov 12 2020 4:50pm
Sorry I had believed that you are on the same hemisphere as I

We are end of season here, and it is easy to forget that some are living where the riding season is about to begin, and others have warm weather al year long.
Yeah I am down in New Zealand, summer is rolling around at the moment. But to be fair, it might pay to wait until our snow season, the Nuclear 24F controller I want to order has a 4 - 5 month lead time anyway!

benjamin84   100 W

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Re: DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

Post by benjamin84 » Nov 17 2020 7:27am

mbgjt1 wrote:
Nov 14 2020 7:57pm
What are you planning to change them to? Yes they are very reasonably priced but if they are limiting your trail rides then it might pay to consider other options. Are you using the DNM RCP-2 on the rear?
RCP-2S on the rear yes :) No complaints on that, but again I'm no world champion. For the forks I would go for some downhill mountain bike forks I reckon, dual or single crown, not sure. Haven't decided wether to keep the bike or sell it yet, powerful e-bikes are getting a lot of attention from the press over here in Norway so I'm feeling less "welcome" whenever I meet someone on the trails than I used to.

John in CR   100 GW

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Re: DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

Post by John in CR » Nov 17 2020 10:20pm

mbgjt1 wrote:
Nov 12 2020 2:55pm
Can't beat the price of the USD - 8 though!
I've got one I picked up 2nd hand but unused, and I can honestly say it's complete crap compared to the used Marzocchi 888's I've bought used, one of which I bought refurbished for $300 from a guy in CA that repairs and rebuilds downhiller forks. Every upside down fork I've ever tried flexes during braking, so the wheel turns left under braking. If you buy one I strongly recommend getting a dual disc system up front.

Pentti M Reku   10 mW

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Re: DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

Post by Pentti M Reku » Nov 18 2020 8:47am

If you are on a strict budget and don´t mind a bit of additional weight, going for a moped front end might be a cheap solution. Steerer should be the same diameter and parts are super affordable.

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MadRhino   100 GW

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Re: DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

Post by MadRhino » Nov 18 2020 9:48am

John in CR wrote:
Nov 17 2020 10:20pm
... Every upside down fork I've ever tried flexes during braking, so the wheel turns left under braking. If you buy one I strongly recommend getting a dual disc system up front.
Some upside down forks are stiff enough to keep straight under hard braking or cornering on the rough, but they are very expansive and still get crooked in a crash. Many DH racing forks can survive crashing without any damage. I have a 2002 Marz Monster T here that had seen a good three dozen hard crashes and still riding. Modern DH racing forks are used on Trial motorcycles now, because they are so much lighter with better tuning precision than any motorcycle fork. The use of bicycle forks on trial motorcycles had started long ago with some pro riders who were doing steer tube mods to fit a Monster T. Nowadays manufacturers are using DH racing triple clamp forks that are factory made for them.
Make it fool-proof, and I will make a better fool.

benjamin84   100 W

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Re: DNM USD 8 vs USD 8s for QULBIX 140r Moto frame?

Post by benjamin84 » Nov 20 2020 2:58am

I come from a motorbike background and thought upside down forks were inherantly better than the alternative as pretty much no performance motorbike designed this century uses them. Then I realised how beefy the WP 48mm front forks on my 500 EXC actually were compared to the DNM USD8 forks.

So yeah, would absolutely stick to regular downhill forks if I was going to swap.

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