There are loads of products that' will clean your leather motorcycle suit. Most of the leathers cleaning products are as good as any in our experience. You can buy leather cleaner products in flagons of 100 to 400ml. You can use them with a damp cloth and soft nylon brush (something like a soft toothbrush) if required to remove as much as possible from the outside and seams. Then spray the cleaner on and rub it well in with a cloth. Finally wipe with a damp cloth.
Linings do get sweaty and smelly and can be hard to clean. If they're removable, you're in luck, put them on a mild wash in the washing machine. If not you can use a helmet or clothing sanitizing spray/product, which will kill some bacteria who case smells and cover any remaining unwanted odor. You can also bundle your leather motorcycle suit up and put them, in a plastic bag, in the freezer for one or two nights. The cold will kill most of the bacteria. Just let your motorcycle suit get on room temperature before flexing them.
It's slightly controversial but we've been told by one expert you can wash leather in the bath tube. Fill it with cool water, don t use detergent and bung them in. Leave them to soak for a little while, then get cleaning with that soft nylon brush again. It's not only a very effective way to get the outside looking clean it will give the lining a good rinse as well. Let them dry naturally and feed the leather with some leather care products afterward. It's worth feeding your leathers after you've cleaned them to add leather conditioning products. You can find a multitude of leather care products on the market, from spray-on's to rub-in's. When feeding leather flex it as much as possible and pay particular attention to seams.