Hey good folks,

May I ask for some advice on a new frame build I am looking to request? I have a decent level of knowledge on biking from past experience but I want to make sure I am doing the right thing with a new frame.

I am 6’4” 380lbs looking to get back into cycling so I can get into shape again. I am obviously having a harder time finding a safe frame. Unfortunately I broke the spokes on my latest store bought build, and i bent the frame when i hit a curb.

Long story short, I am requesting to have a custom frame built using steel that will support my weight. The ask is, are my measurements accurate? This will be a road / gravel frame.

Thank you so much for the advice and help with this, it is greatly appreciated.

The first thing I see is a very high BB height. Gravel riding usually isn't as rough as mountain biking... As to the rest of the dimensions I would refer to the builder's experience and their fitting of you. Andy

Judging by the top tube length and frame angles along with the BB height (no BB drop listed) this is a mountain bike frame with a steeper seat tube angle than is traditionally done. I have converted two mountain bikes to drop bars and can say both of the bikes are wonderfully stable. I believe this is due to the weight distribution being more equal between the axles once the drop bars were installed.

Looks about right to me but your builder will have taken more detailed measurements.

If I were building it I would consider going "double oversize" on the tubes to achieve required stiffness given your relatively high weight and that it's a large frame.

I would also make the seat tube longer (and the top tube closer to horizontal) so you have less seatpost sticking out. (Unless you want a dropper post). It's fashionable to have a lot of seat post sticking out nowadays,.and it gives you a bit of suspension, but it puts a lot of strain on the top of the seat tube especially with a heavier rider. It will probably be absolutely fine I'm just sharing my thinking here! Maybe some things to discuss with the builder.

What Andy said. I'll add that the way I design a frame is based on their bicycle position and I match the frame tubes to that position. I recommend you get a fitting from the builder or one he trusts that knows how to fit those that have a different body shape than when they were younger/fitter and no longer dream of winning the Tour. That fit becomes the basis to create the design. Now of course I recognize that getting fitter through cycling will change your position so your frame design needs to be able to make those adjustments. My guess is that your builder will place your handbars higher (at least as high as your saddle) and put your seat angle further back to make your weight more balanced over the pedals. A shallower seat angle will help take your upper body weight off of your arms and hands. Of course my recommendations are only guesses and not based on the information that can come from a proper fit.

The best thing about Marino bikes- you design it yourself and Marino builds whatever you want. The worst thing about Marino bikes- you design it yourself and Marino builds whatever you want.

I have two of his bikes, a hardtail and a full suspension. I did a ton of research, knew what I wanted, and got the two best riding mountain bikes I’ve ever had.

I had a coworker that designed a terrible bike and that’s what he got.

Build quality is top notch and you certainly can’t beat the price but do your research.

+5. Absolutely good advice. I ride a folder with an ultra-long seatpost and have seen multiple frames fatigue crack right there, front of seat tube above the top tube. This bike is not a folder, but with the rider weight, and just good practice for durability in general, I would go with a level top tube. In this day and age, it also gives a nice retro-style vibe to things. There was a darned good reason for level top tubes for so many decades, it was only when they started counting grams and/or wanted to build fewer frame sizes, that sloping top tubes came into vogue. Go level, go strong, provided you have enough standing crotch clearance with the other dimensions of the frame fitting you. Some folder frames also put a welded gusset in that area, usually on aluminum, but certainly can't hurt on steel either, for what may be the highest stressed part of the frame, in tension, which is where fatigue failures happen, not compression stress. Oh, and simply extending the seat tube above the top tube, only reduces stress on the seat post, but does not reduce the bending moment on the weld zone of the aft top tube weld. Moving that weld higher with a level top tube, does reduce the moment on that weld.

don't forget that wheels and tires will be key to success also Minimum 32 hole (36 better) quality rims on quality hubs, double butted stainless spokes from recognized brand. High end supple tires

I would get an experienced builder to do the design for you. Where are you located? that may help people recommend someone close. My buildier was 1300 miles away, but has the remote customer process solid

the mass quoted suggests tandem loading or ebike.