Look for hardware stores that have the assortments in "little drawers"...about 50% of the time they will have the washer head style metric in grade 8,8 and 10.8.....usually an M8 will be 13mm hex in the usa...but sometimes you can find M12 hex. Stainless and stock bolts are unrated so they are weaker than an 8.8....I put on 10.9 when I can get them..often times the 8.8 grade have M10 hex....but these are REAL hard to find. Look for such stuff at Tractor supply, ACE, Valu hardware sections...FORGET finding them at Lowes or Home Depot....McMaster Carr is less than 50% having them. Oh, yeah...in the little drawers of them, I've never found M8s longer than 60mm
Those stainless steel bolts are OK (pricey), but my solution to finding longer good quality flange head metric bolts is my local Honda car dealership's parts department. The local Ace Hardware has metric flange bolts but they are generic Chinese crap with poorly made threads and rough finishes--not something I trust to hold critical loads or look at and feel like ... Turns out Honda's parts numbering system for bolts is readily decoded, and they use the same parts numbers for both motorcycles and cars. An 8x55 flange bolt is 95701-0805508. High quality Japanese-made, beautifully formed and spec'd. to meet the strength needed here. Call your nearest Honda car parts department, ask for that number, if they don't have it in stock they'll get it usually the next day. I paid about $1.25 per bolt, well worth it. 95701 = flange head bolt 08xxxxx = 8 mm dia. xx055xx = 55 mm length xxxxx08 = thread pitch??? (less certain about this...)
Lots of discussion regarding the pump being cooled by the fuel... For those of you that have added a heat shield when installing your aftermarket tanks, what material have you used? Perhaps you have reused the shields that came on the OEM tank? I have some of that tape that is used on HVAC systems that might help...
Modern fuel pumps in cars and bikes have the fuel run through the electric motor part of the pump, and the pump itself. The fuel cools and lubes the parts. It seems crazy to run gasoline through a DC electric motor, but for some reason, they do not explode. Everything I ever looked at had a fuel pressure regulator outside the pump, in some cars its on the fuel rail and excess fuel returns to the gas tank. The pump runs all the time the motor is turning, and runs for a bit with key on to build up pressure. The pump can supply more fuel and pressure then the motor can use at high rpm's, full throttle, cold engine. Once fuel pressure gets past the regulator set point, it pushes the regulator open and fuel returns to the gas tank. Some cars have/had a vacuum assist on the regulator, open the throttle, vacuum goes away, fuel pressure goes up a bit. Bikes have the pump and regulator in the gas tank as an assembly. Run low/out of gas and there is no fuel to lube and cool the pump and its motor, which has a large amount of plastic in it, and the hot spot is the brushes. They tend to melt their holders.
It turns out the liquid gasoline isn't really as flamable as we commonly believe. It requires the right percentage of oxygen to burn. The 20.2% oxygen in our atmosphere will do it, so we commonly experience flamability. Toss a lit match in an open pool of gas, and it burns. Do the same with diesel fuel, and you get a wet match. This is why many marine engines are diesel engines. They don't catch fire as easily when bad things happen out on the water, far away from help. However, there are lower and upper limits (LEL - lower explosive limit and UEL - upper explosive limit) of oxygen beyond which gasoline won't burn. Too much or too little, and no combustion. (Of course, too high a % oxygen will "burn" all by itself!) A fuel pump emersed in gasoline provides no oxygen, and so the environment is below the LEL. Hence the liquid gasoline can be pumped as an incompressible fluid, and at the same time can be used to transfer heat generated by friction away from the pump, without the danger of "catching fire" in the gas tank. Despite this, many race cars use external fuel pumps (outside of the gas tank) for ease of maintenance and replacement. They pump higher volumes at higher pressures and have a correspondingly higher failure rate. External pumps have been tried on motorcycles, but they are usually more hassel than they are worth, given limited space to place them where they can get enough airflow for adequate cooling. The internal configuration is just more compact and easier to keep cool - as long as you don't run it dry (very often?).
Stock tank insulation. Safari tank insulation. I don't think you could reuse the stock insulation. It probably wouldn't fit well even if you could get it off. I used the foil-backed plastic bubble wrap type and metal-backed tape to hold it on. It's still holding up pretty well after a couple of years of use.
Something like this would also work well. http://www.heatshieldproducts.com/p...-fairing-heat-shields/hp-heatshield-mat/76/35 I've used it to insulate luggage from exhaust heat.
Discount Honda Parts http://www.discounthondaparts.com BOLT, FLANGE (8X55) (95701-08055-08 ) Retail $1.22 Your price $0.99 Order at the bottom of the year-by-year list 'Reverse Part Number Lookup' They will have 10 or 12mm hex heads, never 13mm.
Any Aussies out there scanning this thread for info because they are looking at buying. I have just put mine up for sale. Check out all the info here: http://www.advrider.com/forums/showpost.php?p=19956615&postcount=142
I've had good luck getting individual stainless bolts from http://www.desmoparts.com/ High quality bolts, great selection too. He has kits for some bikes, but a separate page for individual sizes.
In reading this, I had some thoughts since I've had to deal with metric hardware in a sideline project making cam chain tensioners. If you did some digging might find the 8 is a rounded M8-.075 fine thread pitch. They do two fine pitches, M8-1.00 and M8-.075 threads per millimeter. But I'm guessing. The coarse 8mm thread is M8-1.25 threads per mm. Here is a link to the ISO charts I buy bolts at Fastenal, where they can be ordered individually (if not in stock and usually not). Problem is washers and nuts are not sold in singles. Just pointing out the alternative. I am fortunate in having a really good old style hardware store for the goofy or single stuff. I use Fastenal for my quantity purchases though.
Make sure you use anti-seize on them for sure when steel on stainless or stainless on stainless. I am not sure about aluminum. Seems when the bolts/nuts are threaded together the scraping of the surfaces causes some removal of a material that surfaces to avoid corrosion, then the material will bond together - aka sieze up. My brother used stainless for a nut/bolt pinch clamp on a Betor fork axle clamp. They seized and he had to snap the bolts to get them off. I'd certainly check on the aluminum/stainless reaction to be sure. Here's Fastenal's take on it. Here's another expert's take from an expert in the industry based on what I've found on a net search, Joe Greenslade.