We are leaning toward to Alpinestar GP-T suit. As far as measurments they are: Height 6'1" / Weight 175-180 / Chest 40 / Hip 41 / inseam 29. Closest I could find would be size 54 - advice? His usual pant size is 32/34.
I dont know that this brand will fit him properly. The length is good but very big in the back and sides. It also gives him a major wedgy. So I would be afraid to go any smaller. If you have any suggestions, I would love to hear them.
A couple similar suits that might fit better would be the or the . Alpinestars suits in particular are known being slim cut which would likely alleviate the "bagginess", but staying about the same length.
On the other hand, often if the length seems fine, but the suit pulls up too much during moving around (wedgies) it's often a sign that the torso length is too short. This could possibly be eliminated going to a different brand such as the Alpinestars. If not, he would be best off with a . This will let him size his torso separately from his legs as well as allow the two articles to move without tugging.
Can you advise on his height and inseam? This would help the most in figuring out a better suit. (Inseam in this case is a direct measurement from bottom of crotch to bottom of the leg/top of the foot.)
With those dimensions I would recommend a 54 as well. It will fit his chest and waist more appropriately. It also should fit fine on his inseam and torso length as well, however, this will be best judged by him trying it on.
The Oakley suits should fit fairly similarly- their sizing is based off of Sparco's which is close, but shifted up a size.
He would be looking at a Large (56) in the Oakley which is equivalent to the Alpinestars 54.
In my experience, the Alpinestars suits are the slimmest fitting. Oakley would be a bit looser and both are much slimmer than the K1.