Sur-Ron - New Mid drive Bike

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Offroader   10 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » May 01 2019 9:55am

Are air forks really out of the question. They have NEW 2018 Fox 40 factory float for $895.
It looks like the 26" version is being discontinued and they are dumping them :cry: . This could be the last time you can buy a fox 26" fork.

https://www.ebay.com/itm/NEW-2018-FOX-F ... 0#viTabs_0

I know there are some draw backs with fox forks like having to do frequent maintenance and oil changes. It would be really cool to ride around with a fox fork especially since I"m going to be in Manhattan a lot with the bike and it gets a lot of attention. I always look at the mountain bikes with fox forks and wish my bike had one, even though they may not be better than other options.

Worst case I could probably always sell this and get a reasonable amount of my money back, all these forks seem to sell well as they can be upgraded with better cartridges and possibly coil conversions.

What do you think, should I go for it? Or do you guys think I should stay away from any air sprung fork at all costs and stay with coil since we are using ebikes?

I am probably leaning towards the X-fusion otherwise. I want to avoid upside down forks because of the flex so I may pass on the Manitou. I noticed with the DNM inverted fork that the front wheel wobbles when riding at high speed on the street as there is no support brace.

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Re: Sur-Ron - New Mid drive Bike

Post by dirkdiggler » May 01 2019 11:04am

I just bought a dnm, to replace the fastace after a year of riding. Blown seals. I had an x-fusion rv1 on auction that got snipped for $350. Another fork that might be good is the marzocchi 380. It's made by Fox. They sell for $500 new on eBay.

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » May 01 2019 11:33am

DNM is same crap as the fast ace. I had a DNM that I broke after dropping the bike and pushing off on the handlebars so I would avoid falling on the ground when the bike was on its side. The leverage caused by doing this twisted the stanchions. I was able to loosen the crowns and twist it back but it never felt smooth again.

This is why I avoid inverted forks, and the other reason is that I can feel the front wheel wobble at high speeds because without a cross brace near the wheel the stanchions are not stiff enough to keep everything stable and not twisting.

Looks like that fox 40 float 2018 model isn't as updated as the new 2019 fox 40 float. They don't sell a 2019 26" version anymore, so only the older 2018 version is still available in 26".



While the 40-series Fox forks have received some small incremental improvements over the last few years, they had yet to receive any ground-breaking improvements to really set them apart from the masses. That all changes with the 2019 Fox 40 GRIP2 fork, which is sporting Fox's brand new FIT GRIP2 damper.

FIT GRIP2 Damper
Those of you familiar with the 2018 Fox fork lineup may recall the GRIP damper being associated with the lower-tier forks - and you would be correct. This is a case where technology has trickled up instead of down. Fox's no-nonsense GRIP damper was based off the technology used in motocross, and quite simply, it was reliable, bombproof, and worked very well. So much so that Fox decided to scrap their tried-and-true RC2 damper that they've been using in their forks for over a decade. The GRIP2 is based off the GRIP damper, but improved and tweaked in several ways. Most notably, it features 4-way adjustable high/low speed compression and high/low speed rebound. This is a first for any Fox fork. Previously, the RC2 damper featured 3-way adjustability (high/low speed compression and low speed rebound). That means the GRIP2 is the most adjustable damper Fox has ever produced. Just how adjustable you ask? Well, we've got 15 clicks LSC, 27 clicks HSC, 16 clicks LSC, and 8 clicks HSR. That gives a very broad range to tuneability to accommodate just about any rider preferences. For some, it may seem a bit overwhelming, but don't worry, Fox has suggested base settings printed on a sticker on the back of the fork to help you out.

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Re: Sur-Ron - New Mid drive Bike

Post by liveforphysics » May 01 2019 1:00pm

Fox40 is so much better than every other mt bike fork I've ever experienced, it's got no practical competition if you're looking for the best fork option (IMHO). Whatever it costs is just what it costs to have the best fork if that's something you want for your bike.

Just my $0.02, I know everyone has their own opinion on suspension.
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Re: Sur-Ron - New Mid drive Bike

Post by morati » May 01 2019 3:31pm

liveforphysics wrote:
May 01 2019 1:00pm
Fox40 is so much better than every other mt bike fork I've ever experienced, it's got no practical competition if you're looking for the best fork option (IMHO). Whatever it costs is just what it costs to have the best fork if that's something you want for your bike.

Just my $0.02, I know everyone has their own opinion on suspension.
Agreed! Been using mine now since 2015 and nothing else I have ever ridden comes close. I paid alot for it but it was worth it IMO.

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Re: Sur-Ron - New Mid drive Bike

Post by Grantmac » May 01 2019 4:07pm

Why not machine a triple clamp to take "big wheel" kids MX bike forks? Like you'd find on a 105sx, kx100 etc?

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Re: Sur-Ron - New Mid drive Bike

Post by liveforphysics » May 01 2019 4:54pm

Grantmac wrote:
May 01 2019 4:07pm
Why not machine a triple clamp to take "big wheel" kids MX bike forks? Like you'd find on a 105sx, kx100 etc?
Because they weight a lot more for much shitter suspension feel, and require more custom labor and work to install just to arrive with a heavy shittier front end. Yes, good kids MX bikes forks do exist, but they cost as much or more as a Fox40 and still would be doubtful to outperform it. (Granted, I may be biased because I used to work right next to Fox RnD and got to see the incredible testing they do on their products with respect to suspension performance and durability.)
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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » May 01 2019 8:40pm

madin88 wrote:
May 01 2019 5:21am
Offroader wrote:
Apr 30 2019 8:20pm
If it was only so easy then why would they sell two different versions of the same fork in 26" and 27.5".

I really don't know and need to figure this out.
Forks for larger wheels usually have more offset which will change the trail of the wheel.
If someone would adjust the mounting position of the crowns from a 29" fork it wont be the same as a true 26" fork.

If you would put a small wheel into a 29" fork it would have a very low trail and therefore bad handling (at higher speeds), which is basically the worst thing you can do for a bike capeable of speeds close to 100kmh.

Regarding X-Fusion, i have bought one of the 26" RV1 from the link posted here recently (about 380€ shipped to my door from Taiwan), and all i can say so far is that it has almost no stick-slip or stiction - even with some weight on it.
What i really like is the independent low and high speed compression settings which work MUCH better as on the latest Rockshox Charger 2 Dampers for instance. I could compare a Boxxer and Lyrik (the latest ones with debond air spring) with the X-Fusion and guess which fork i did like better :)
-> Don't listen to theire marketing bullshit and probably sponsored reviews and test reports from the internet!

I was also looking for a used 26" R2C2 boxxer (which are availale around 300-400USD), but now i would always take again the X-Fusion RV1 if you could find it for the same price.
The only downside is that it comes with a very soft spring and replacement springs cost around 60USD (i bought the extra firm spring).
Why did you decide to replace your Sur-Ron fork with the X-fusion?

Did you have the Killah fork? Were you not happy with that fork?

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Re: Sur-Ron - New Mid drive Bike

Post by Grantmac » May 02 2019 11:37am

liveforphysics wrote:
May 01 2019 4:54pm
Grantmac wrote:
May 01 2019 4:07pm
Why not machine a triple clamp to take "big wheel" kids MX bike forks? Like you'd find on a 105sx, kx100 etc?
Because they weight a lot more for much shitter suspension feel, and require more custom labor and work to install just to arrive with a heavy shittier front end. Yes, good kids MX bikes forks do exist, but they cost as much or more as a Fox40 and still would be doubtful to outperform it. (Granted, I may be biased because I used to work right next to Fox RnD and got to see the incredible testing they do on their products with respect to suspension performance and durability.)
But how good are bicycle components when used way beyond their engineered intent? Not to mention that the class of motorcycle I'm talking about is miles away from a kids play bike but rather an extremely competitive class for young teens. Hardly a place where crappy suspension is acceptable.

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Re: Sur-Ron - New Mid drive Bike

Post by liveforphysics » May 02 2019 4:27pm

Grantmac wrote:
May 02 2019 11:37am
liveforphysics wrote:
May 01 2019 4:54pm
Grantmac wrote:
May 01 2019 4:07pm
Why not machine a triple clamp to take "big wheel" kids MX bike forks? Like you'd find on a 105sx, kx100 etc?
Because they weight a lot more for much shitter suspension feel, and require more custom labor and work to install just to arrive with a heavy shittier front end. Yes, good kids MX bikes forks do exist, but they cost as much or more as a Fox40 and still would be doubtful to outperform it. (Granted, I may be biased because I used to work right next to Fox RnD and got to see the incredible testing they do on their products with respect to suspension performance and durability.)
But how good are bicycle components when used way beyond their engineered intent? Not to mention that the class of motorcycle I'm talking about is miles away from a kids play bike but rather an extremely competitive class for young teens. Hardly a place where crappy suspension is acceptable.
They make some killer stuff that would be awesome for it in the competitive big wheel bikes. For some reason I thought you were talking 4 stroke pit bike front ends, and that was entirely my bad not reading what you clearly wrote, my bad. I bet it would be an awesome upgrade if you need more strength than the fox40. You're right they would handle more abuse before breaking than the Fox40 I bet. It would also give a serious front brake upgrade running the MX bike brake setup. It would be interesting to see the weight differences.
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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » May 02 2019 4:32pm

pretty sure thats not a problem if the weight of the bikes are below 60kg.
why?

check trial bikes. 70-80kg and a trial bikes fork is similar to a dh fork.
from "junior" bikes they even have same bearings.

when you dont want to trust a fork i agree on all USD mtb forks. theres a reason why you dont see any usd fork on a professionel rider.
clamp the frontwheel between your legs. now twist the handlebar.

pretty easy your handlebar can be moved 10.....ten centimeters in both direction. they flex as frock.
when you brake hard and watch over the handlebar you can see how the fork bend and the frontwheel leans to the left (disc) side.

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Re: Sur-Ron - New Mid drive Bike

Post by Grantmac » May 02 2019 4:53pm

I'm talking the forks with 10" of travel found in the category of bike running a 19" front rim. KX100, 105SX, CRF150RB. They aren't expensive on the used market and the brakes would be a serious upgrade.

You have to be careful looking at Trials forks. They are bigger than DH forks but aren't designed to take the same kind of high speed hits at all. Perhaps if used on a much lighter bike they could but even so they have very little rebound dampening. Also rather rare compared to MX stuff.

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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » May 02 2019 5:29pm

i dont know íf whe can compare...but jumping all day long on flats and drops sounds pretty even to me (mx/trial)

i was riding years 19" motorims on DH Forks..just because preventing flats + stable at higher speeds.
but in the meantime i prefer 26" mtb wheels. saving 2,5kg roating mass and 26" is similar to 21" motowheels....they roll way better offroad.
iam more offroad addicted than street. sometimes yes. i was afraid of heavy abuse the magnesium, aluminium lightweight fork holding my 5,3kg frontwheel at 40-50mph on a wheelie and bashing it without rotation down to the street.
But.....looks like it works :D
if your long enough on the sphere seeing some guys putting even 10kg hub motors on the front and still alive.

about the brakes. your right if it comes to speed or heavy ebikes.
i had no issues on my 65kg big ebike but only because of ebrakes. if i had no regenbraking option i would need every week new brakepads.

adam from lmx found a solution. TRP brakes with thicker discs + better pads. i had all that mtb stuff....shimano, magura, hope. all in biggest 4 piston option.....until now i thought "those mtb brakes" cant be better. i dont know if its about the pads or the 2.3mm thick disc.
but these brakes top all other brakes out. one finger needed for stoppies.

of course an mx fork with mx brake would be incredible braking power...but i think they would be overkill like moto tires on our lightweight bikes.
you need thousands and thousands of miles to wear out a tire.

in case of a fork you add serious weight.

what should i say after riding years those heavy rear hub monsters............WEIGHT is the baddest thing you can add to your bike.
i will try to find out how much a (trial)fork weights.

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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » May 02 2019 7:33pm

5Kg without triple clamps...

https://www.rideformula.com/products/mo ... -standard/


so you wanna upgrade? easy. take FOX40 clamps,
find or build simply a 0,5mm washer for the 39mm stanchions
and you can use any trial frontwheel and brakes.

or....
trial front wheel hub,
lacing with a great DH rim and you can ride mtb tires again.
saving the heavier wheel with the benefit of using a trials fork + bad ass front brake.

normal MTB fork has 3Kg. that means +2.5kg for the fork and probably +500/750g for the brake and disc
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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » May 02 2019 7:40pm

...but i think iam well served with a stock Fox40 =)


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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » May 02 2019 8:19pm

I think the reasons nobody uses mx or dirtbike forks is there is not much reason to.

The downhill forks are more than fine and hold up to the abuse and they are light weight.

We dont have ebike racing competitions and no reason to push the limits of down hill suspension.

We for the most part always had hubmotor bikes before the surron and the rear suspension limited us far before the fork.


.

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » May 02 2019 8:51pm

After long deliberation I made my decision on buying a sur ron fork.

I was liking both the fox 40 float and the x-fusion also the dvo emerald.

The fox 40 is discontinued in 26 size and is only available in a 2018 model. I really want to test out a good air spring fork and this fork will make my bike look expensive. However air spring is inferior to a coil from my research.

The x-fusion is probably the best 26" coil fork you can buy new.

DVO emerald was hard to justify because it was so expensive.

I decided to just buy both of them as the deals were really good. Now I can have some fun and see if different forks make a difference and if there is any benefit to having the adjustability of an air fork.
Curious to see if the fox hype makes any difference.

I also puchased the cane creek 40 headset and extra crown races.

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Re: Sur-Ron - New Mid drive Bike

Post by madin88 » May 03 2019 10:19am

Offroader wrote:
May 01 2019 8:40pm
Why did you decide to replace your Sur-Ron fork with the X-fusion?

Did you have the Killah fork? Were you not happy with that fork?
This fork was not for a SurRon bike.

I want to say again something about the latest forks from Rockshox as i had two in hand for comparison. The Boxxer RC (2019) with debond air spring and Charger 2 damper (low speed setting only), and also a Lyrik with Charger 2 RC2 damper (high and low speed compression settings).
I did not do any riding with them, but i have installed the hub in each and did some tests by hand. What i noticed on the Lyrik was that it went down almost 20-30mm in travel after realeasing the air (0 PSI). The reason for that probably was that air was already leaking into the negative air chamber, so there seems to be high risk that you loose travel and pressure over time and you probably have to disassemble the air spring to let the air out from there. The other thing was that from the advertised 80% reduction of stick-slip or stiction i could not feel anything.

The RV1 has strongly impressed me especially at a price less than half of the other two.

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Re: Sur-Ron - New Mid drive Bike

Post by Tommm » May 03 2019 3:27pm

You can get a host of different spring strengths on ebay for x-fusion:
https://www.ebay.com/sch/i.html?_from=R ... rv1+spring

For the sur ron you might need a firm or x-firm, or a xx-firm if you plan on jumping it. They come with the normal strength as new unless specified.

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Re: Sur-Ron - New Mid drive Bike

Post by freeflow » May 04 2019 12:55pm

What do you think about using the Ohlins ttx as a rear shock?

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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » May 04 2019 1:25pm

Just a money thing.
The dnm is low cost stuff and it is mostly OK.
If the cash is no problem go for it.
If it's bling factor go for it.
If you take serious jumps switch anyway the dnm :)
The dnm have no end progression. The frame linkage have.
But buttom it out can end in breaking the linkage.

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Re: Sur-Ron - New Mid drive Bike

Post by freeflow » May 04 2019 1:51pm

The idea is to jump it and ride it hard, at least not end up with a bike that cannot take a beating. I would get it at half price, taken in account that I might need to replace the spring for a higher weight. The shock has been sitting on a Specialized Demo 8.

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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » May 04 2019 2:00pm

Pretty sure you need harder spring.
Stock l1e has 450lbs. For my 56kg girl ok.
When I ride it my ass wobbles all time on the bottom out rubber at the end of stroke 🤣

Not sure with ohlins but some of them have not the common 8mm bolts. They have a special mounting point that doesn't fit all other dh bikes.

Surron also needs 267mm or 10.5 inch shocks
It's rare these times. Most have 241mm/3.00-3.25

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Re: Sur-Ron - New Mid drive Bike

Post by freeflow » May 04 2019 2:12pm

This one was 240mm which I thought was what the Sur had, well well then I will need to keep looking.

Thanks for the response

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Re: Sur-Ron - New Mid drive Bike

Post by trazor » May 04 2019 4:59pm

I hear these long rants about forks and quality and durability and dream about 10 meter jumps you are doing with you bikes. I think it is time to begin posting what we are talking about. For example, here is how I twisted my DNM forks. I can re-clamp them but after any other big hit they come back to twisted position. Anyway, I'm happy with them because is what I can afford and ride without fear of trashing more money than I can spend.

https://www.youtube.com/watch?v=tr-LoRF ... u.be&t=457

If you check the video, my front tire was flat, that was one problem when braking, the other problem where between the seat and the handlebars.

And here is how I broke a Marzocchi 380 2016 https://www.youtube.com/watch?v=eYrMMuwD9jI
One leg got stuck and I had to pull it out and remove one bushing (the bottle was slightly bent breaking bushing alignment). It works until this day with 3 bushings and I don't feel any play :lol:

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