1st Build: TanTan/Seraph GR029 with Sensah SRX Pro 1x11

[ChrisB]

Thank you for the admission to this board.
After positive experiences with Chinese carbon wheels, we decided to research the possible build of a Road/Gravel bike for my girlfriend. Chinertown gave some hints on what to look out for and which suppliers to choose for our project.
The goal was to build a bicycle mainly for the use on tarmac with some lighter gravel, therefore had to have clearance for wider tires.
Finally we decided on following components for our build:

Frame and Fork:
TanTan / Seraph: GR029 with 15mm Fork and BSA BB in size 52
We ordered the matching headset and thru axles directly with the frame to prevent any mismatch.

Groupset:
Sensah SRX Pro 1x11
Crank Zrace RX 172.5mm long with 44 chainring
Casette Zrace 11-46

Brakes:
Ordered seperately Zrace cable actuated hydraulic disc brakes for 160mm rotors.
The sets normally offered on Aliexpress only include adapters for 140mm discs which do not work for our terrain.  ;-)

Seatpost and saddle:
Ordered a separate carbon seat post 27.2mm and a saddle in "Specialized Mimic" style.

Wheels:
We still had a set of Alexrims with Schwalbe X-One 33mm tires laying around to be used.
The disc rotors are some standard Schimano.

Some additional parts such as brake and shift cabling were sourced locally.
The Fizik Cyrano bars in 420mm width and 110mm stem completed the build.


Additional remarks:
The frame was ordered mid of October and we requested a specific custom paint.
Communication with Seraph was excellent over Aliexpress. They sent us a CAD drawing with the custom paint for our confirmation after 24 hours, which is great service.
They let us know that the paint job would delay the shipment for about 20 days, which was about correct.
Due to the reduced air shipment choices caused by Covid-19, the shipment was rerouted and finally left china around the 9th of December 2020 and arrived in Europe end of December.
The quality of the frame and custom paint is very good. The only complaint is that the whole in the fork for the axles were not perfectly protected during painting so some colour entered, which I had to remove before assembly.

The assembly went pretty smooth without bigger issues. Inner cable routing always presents a challenge so you should have the right tools at hand.
Cable routing was done using a Zitto routing tool that is similar to the much more expensive Parktool counter part. For around 10US$, I can highly recommend it.  :-)

The Sensah groubset works well especially the shifting is very nice.
The break power needs to be checked once we had the chance of some extensive rides.
But make no mistake it is certainly not on the level of Shimano hydraulic disc brakes but we expect it to be OK for relaxed riding.

The total bike including Shimano SPD pedals is at 9.065kg which is not too bad considering the 33mm wide tires and quite heavy wheelset.
Going with some nice carbon wheels and tubules would certainly be a big improvement.  ;-)
The cost for the whole build was around 1000US$ including shipping, import taxes and additional parts.
Not super cheap but a real fun project with good result.  :-)

Some things still need to be fixed:
- For correct crankset mounting you need to use spacers adjusting the side to side play and preload of the BB. Unfortunately the shims in the set do not fit perfectly leaving about 0.5-0.8mm play. We will have to source a matching shim to correct this.
- There were only 4 instead of 5 screws speed to fix the chainring to the crank. It seems some mountain bike chainrings only use 4. We did order some additional parts to fix it.
- The cable routing for the rear break is not perfect on the first try so we have some slack and soft feeling when actuating the rear break. This should be easy to correct.

No riding experience yet due to the points to be fixed and cold and wet weather.
We will report our experiences at a later point in time.

[Tangerined]

Cool! Been thinking of building with this frame as well. Looking forward to hearing how the frame holds up.

[carbonazza]

Nice build !
I have a couple of questions:

Brakes:
Ordered seperately Zrace cable actuated hydraulic disc brakes for 160mm rotors.
The sets normally offered on Aliexpress only include adapters for 140mm discs which do not work for our terrain.  ;-)

Where did you order if not by Aliexpress ?

Additional remarks:
Due to the reduced air shipment choices caused by Covid-19, the shipment was rerouted and finally left china around the 9th of December 2020 and arrived in Europe end of December.

What transporter did they use ?

[ChrisB]

Hi there

Nice build !
I have a couple of questions:
Where did you order if not by Aliexpress ?


What transporter did they use ?

Brakes:
I ordered the groupset without brakes and added the brakes for 160mm discs separately from the same seller on Aliexpress. The sellers name is "Discount Bike Store".
The shipment took some time since they did not have the 42teeth chainring. After contacting them they let us know they ran out of 42 and offered a 44 chainring which they had on stock for immediate shipment.

Transporter of frame:
We used the standard they suggested which turned out to be EMS which is a common parcel service in Europe.
Usually not an issue but now before Christmas and due to the pandemic it was all delayed.

[carbonazza]

Thanks for the response.

ZRace have a shop too on Ali, and are quite responsive too.
But they can be more expensive.

With EMS you're almost guaranteed to get a 48,5% antidumping tarif.
I haven't tried it in a while, but that was the norm in Belgium.

[ChrisB]

No problems with Tariffs with my EMS packages from China so far.
Just payed the Swiss VAT on the frame value, so this is absolutely OK.

[svanimpe]

Cool! I was thinking of building a similar bike for commuting.

- Is this the 2019 or 2021 model of the GR29? I've seen this frame both with one piece derailleur hangers (like yours), and with two piece derailleur hangers (which I absolutely want to avoid). It's unclear to me if this is due to the different model years.
- What type of brake outer cable are you using? I'm worried about the braking performance, as that seems to be a common complaint with this combination of Sensah shifters and cable disc brakes.
- Did you buy the frame from the "SERAPH Official Store" on AliExpress?
- How much did they charge for that paint job?

Definitely let us know if/how you fixed the play in the crankset/BB.

[ChrisB]

Hi there

Cool! I was thinking of building a similar bike for commuting.

- Is this the 2019 or 2021 model of the GR29? I've seen this frame both with one piece derailleur hangers (like yours), and with two piece derailleur hangers (which I absolutely want to avoid). It's unclear to me if this is due to the different model years.
- What type of brake outer cable are you using? I'm worried about the braking performance, as that seems to be a common complaint with this combination of Sensah shifters and cable disc brakes.
- Did you buy the frame from the "SERAPH Official Store" on AliExpress?
- How much did they charge for that paint job?

Definitely let us know if/how you fixed the play in the crankset/BB.

- Ours should be the latest version of GR029 (20/21) and there was no choice in terms of derailleur hanger so I guess this should be standard.
- We used a Jagwire break cable set with the standard outer cables that comes in the set. We have only used the outers until it enters the frame and where it exits the frame. In this configuration the brake activation does not need a lot of force and break force is good.
- I ordered the frame from Aliexpress in their "Seraph official store"
- The two tone paint job with two Pantone matte colours was 80 US$.

- After checking the parts of the crank again, I found two thin steel washers. Placed on both sides  of the crank and removed the remaining play in the system, so all good on that front.  :-)

- I found another small problem with the screws shipped to fix the ZRACE cable activated disc brakes. The screws are too short for this frame so they hold on to only 3 turns of the thread. I will replace them with standard M5x35mm so they will properly fix the brakes to the frame.

All in all I think the frame is a solid product at a fair price.

[svanimpe]

- I found another small problem with the screws shipped to fix the ZRACE cable activated disc brakes. The screws are too short for this frame so they hold on to only 3 turns of the thread. I will replace them with standard M5x35mm so they will properly fix the brakes to the frame.

Yeah, I messaged ZTTO about this (who also sell the same brakes). They said the brakes include only one set of bolts.
Can you check the height of the chainstay at the rear flatmount?

[ChrisB]

The M5 screws that come with the ZTTO kit are 30mm long.
For the GR029 M5x35mm bolts should work perfect.
I will get them this week to fix the rear break mount.

[dpitel]

The M5 screws that come with the ZTTO kit are 30mm long.
For the GR029 M5x35mm bolts should work perfect.
I will get them this week to fix the rear break mount.

EDIT: Sorry about the huge pics, I haven't posted on forums, with the exception of reddit since my late teens/early 20s.


Let me know how you like the groupset- I just got my SRX Pro today and I'm in the process of putting it all together- not sure when I'll be able to ride it as it's snowing in NY (where I live) but the shifters feel WAY more solid than they have any right to, considering I got the shifters and rear mech for about $150USD. I'm running it with a 48 tooth narrow-wide chainring ($25 Amazon special, lol) and an 11-42 cassette out back. Not using a Chinese frame, though, this is on my Trek 1.5 and I'm planning to use it as an all-around training bike to experiment with 1x and just have a project. I have a R7000 2x11 on another bike so this is purely for fun- when i saw the price and read the (usually) good reviews, I decided to pull the trigger. I'm running an 11-34 cassette on my 2x11 and it's nearly as heavy as my 11-42, so if I like this 1x thing, I can splurge on a lightweight 11-42 or 11-46 off of eBay. BTW, your GF's bike is dope! Do you have any idea how heavy your cassette is? my SunRace is 412 grams, whereas according to Shimano's site (I'm too lazy to pull mine off the hub and weigh it) the 11-34 is 379 and eBay has some of the 11-42/46 that are under 400 and i *think* are less than 379 grams. Speaking of weight, do you know how much the finished build weighs?

Here's a pic of the mini-group and the frame as it stands ready to be built up- if there's any interest, I'll post pics of the complete build probably tonight or tomorrow. BTW, nice to meet you all, my name is Dmitry.

[ChrisB]

Hello Dmitry

Unfortunately still no long ride with the bike due to snowy conditions here in Switzerland. I guess that the current weather is comparable to NY at the moment.  ;-)
But the shifting feels crisp so should not be an issue. The Zrace brakes are the thing that I am more concerned with, they definitely need more force to activate than Shimano Hydraulic discs.

Thanks for the compliment she is really happy with the bike, especially with her chosen colours.  :-)
The full bike weighs in at 9.06Kg, with some lighter wheels this could go below 9kg I guess.
Unfortunately I did not weigh the 11-46 cassette separately. But it seems to be pretty light for this size.

I recently bought a super light Zrace 11-34 Cassette that weighs in at 230g Vs. 306g of an R7000 11-32 Shimano.
So some of the Chinese parts can offer a weight advantage. The durability needs to be proven in the coming season...

I installed the Zrace 11-34 on my Merida Speeder which I modified to a Gravel bike.
I bought Elite 32mm x 35mm Carbon Wheels and 35mm Panaracer SK tires to complete the build.
The Merida comes in at 9.17Kg including pedals.

Looking forward to see your Trek finished with the 1x setup, curious about the weight when finished!

[NorthboundRick]

EDIT:Here's a pic of the mini-group and the frame as it stands ready to be built up- if there's any interest, I'll post pics of the complete build probably tonight or tomorrow. BTW, nice to meet you all, my name is Dmitry.

Second picture. I really like the nomenclature of your parts storage system.  . How does a drawer earn the s**t classification?

[dpitel]

Hello Dmitry

Unfortunately still no long ride with the bike due to snowy conditions here in Switzerland. I guess that the current weather is comparable to NY at the moment.  ;-)
But the shifting feels crisp so should not be an issue. The Zrace brakes are the thing that I am more concerned with, they definitely need more force to activate than Shimano Hydraulic discs.

Thanks for the compliment she is really happy with the bike, especially with her chosen colours.  :-)
The full bike weighs in at 9.06Kg, with some lighter wheels this could go below 9kg I guess.
Unfortunately I did not weigh the 11-46 cassette separately. But it seems to be pretty light for this size.

I recently bought a super light Zrace 11-34 Cassette that weighs in at 230g Vs. 306g of an R7000 11-32 Shimano.
So some of the Chinese parts can offer a weight advantage. The durability needs to be proven in the coming season...

I installed the Zrace 11-34 on my Merida Speeder which I modified to a Gravel bike.
I bought Elite 32mm x 35mm Carbon Wheels and 35mm Panaracer SK tires to complete the build.
The Merida comes in at 9.17Kg including pedals.

Looking forward to see your Trek finished with the 1x setup, curious about the weight when finished!

Hey, I finished the build a week or so ago, but I only put nine or so miles on it- those nine miles were really impressive though- the shifting was nice and smooth- I've never ridden a bike with a SRAM groupo but everyone says that's what these shifters basically are. Very light and precise shifting- both up and down the cassette. Without pedals, the bikes weighs in at 7.9kg/17.4lbs- which is pretty good IMO for an 11 year old alloy frame with the stock carbon fork (going to invest b/w $50-$75 in a new carbon fork w/carbon steerer to drop another 100-150 grams off this beast). I just ordered a 2016 Emonda SL frame this morning so that's going to be me budget weight-weenie build, but I also bought some carbon wheels that weigh 1340+/- grams last night and some nice tires this morning (both of them add up toe 415 grams on my scale) so with those wheels and the new fork, I'm confident I'll be able to get it to under 17lbs and maybe mid or possibly low 7kgs.

I promised pictures and I'll deliver- it's been snowing so I don't have any outside pics so here are two pics- one that's been ruined with filters and all that shit that I posted on instagram and the original. I'm thinking of trying to remove the decals off the wheels b/c a) I go between thinking they look cool with the green of the bike and super lame and b) they look weird as fuck on my other bike which is blue and will look weird as fuck on my Emonda which is black.

[ChrisB]

Hey that looks great and the weight is quite impressive for a bike of this age.
The stickers on the wheels are a bit too flashy for my taste... but sometimes it is a pain to remove stickers if the manufacturer used a sub par glue.

What kind of wheels do you have on order?
I hope some Chinertown conform species...  ;-)

The Emonda SL frame also sounds interesting, what groupset do you plan to use?

Have a great weekend!