KHS 747 Flite 67cm XXXL Road 2014, Diamond Back Ascent EX MTB/Commuter 1992
KHS 747 Flite- More Component Issues- Bent Seatpost
I am really loving my new KHS 747 Flite as the fit for a 6 foot 8 240 lb guy like me is great.
Unfortunately, I am running into more issue with the stock KHS components not properly suited for the Clysdedale riders the bike is designed for. You all may have seen my earlier threads where the 52tooth front chainring bends and needs to be replaced with a stronger piece. Now after less than 200 miles on the bike, the latest component failure is the seatpost. It is a "Q2" setback seatpost from KHS. I was thinking about getting a straight seatpost anyway to shorten the reach a bit. I am all legs and the XXXL 66cm frame is a tad long for me so getting a straight seatpost would shorten the reach by 1.25 inches. I already replaced the 130mm stock KHS stem with a shorter one, but that was my choice and not an issue with the bike.
I decided to look at the stock seatpost before ordering my replacement and pulled it out of the frame only to notice it is bent back in a nice curve shape now. This bend is not the stock "setback" bend but has actually fatigued to the point it is bent in a gentle "C" shape after only 200 miles. I tried to shove it back in the frame and confirmed it's bent as it won't slide in past the point where I had it before. I can't force it any lower without re-bending it back to it's original "pre-bent" shape. So, like the chainrings this component seems to be too weak for Clydesdales.
I just received and installed a BBB "Skyscraper" 29.8 x 400mm straight seatpost I bought on eBay. The best 29.8 x 410 seatpost is a Thomson, but they discontinued that diameter/length combination, that is why I bought the BBB. It seems pretty strong and not being a setback should have less rearward-force to promote bending. So the new seatpost was $40, plus the $185 I spend on the Praxis Forged Chainrings for the other issue putting me up to $225 to re-engineer the bike properly.
I am still positive overall as I have a road bike I can actually use. I have been so used to re-engineering stuff for my size over the years that it doesn't surprise me, but I am disappointed that KHS has sourced such weak components for a bike supposedly designed just for Clydesdales. I would have gladly paid $1,999 for the bike and had it "right" out of the box rather than to keep having these issues. I am hopeful the rest of the bike will hold up well.
I believe most of those inexpensive 400mm posts are made by kalloy, I've used an origin8 version without issue with a ton of it sticking out (the seat tube length forced me to have one for proper min-insert)
if that ends up not working out a seatpost shim and a thomson are where I would move (or find a used thomson if you can find one of the proper dia)
Hmm. I'm a total newb trying to decide on big bike. I'm 6'7" 240 and wondering - for the price you had to add to the KHS - would a custom Gunnar come out around the same amount? I'm off to my LBS tomorrow to talk options.
I had the same thing happen on my 747 XXXL that I purchased in march. I replaced it with the Thomson 410 mm straight post (I believe I bought the last one available anywhere at the time--I was insanely fortunate), and I addressed the resulting reach issue through bar and stem adjustment. (I'm 6'10"). So far the Thomson is an absolute dream. I'll be interested to hear what you think of the BBB. I hadn't heard of it until your post. If I need another one, I'll be sure to check them out.
Overall, I wholeheartedly agree that the seat post that comes with the bike is not up to snuff for the bike's intended purpose. Not even close. KHS made a big blunder there. Fortunately, the Thomson is more than up to the task, and it sounds like the same is true of the BBB. But still, the change shouldn't be necessary.