| Author | Message | ||
     Whodat |
Howdy. Just bought a blast as a kid/loaner bike (actually I traded a VFR700 for it) and the bike I got came with an aftermarket exhaust and the PO stated that the guy he got it from said it had the 515 kit. I take it for what it's worth. I get it home, look at the bottom of the carb and see that it still has the idle air screw cover, figure it's all bone stock and I should probably jet it. I read up here, find that the collective recommends a 170 main and a 45 pilot, so I order those. I also go ahead and shim the needle .050ish. The jets are slated to arrive today so I go ahead and pull the carb. Yank it apart and lo! it already has 175 main and a 42 pilot. I do some google fu and only find that combo listed with the 515 kit. So, long story shorter: is there any way to tell whether or not it has a big bore kit without pulling the head and measuring? I could only find one mark on the cylinder, on the edge below the carb. Looks like a number in an oval, possibly 193. I've looked at pics on the innernats and can't find any particular consensus other than that some have an HD stamp on them. I want to put it all back together so my son and I can go riding, but I'm not sure whether to put the 175 back in and assume it has the 515 or go with the 170 and chance running it lean. Also the front upper motor mount is shredded, any consensus on where to get a new one? | ||
| Gearheaderiko |
Depends on the 515 kit. A picture would help. 515 kit is only a .060" overbore. Jetting is 45/170 or 175. 2 shims. That's going to be on the rich side. But keep an eye on it. Some 515's were very unreliable, listen for Knock or ping. Jetting won't be far off from those number. Screw cap still on the carb does indeed indicate a stock motor. But you never know (as you surmised)! A silver cylinder is almost certainly a 515. | ||
| Whodat |
Cylinder is black. I scraped the paint off and in one direction it looks like 153, in the other it looks like EST. This is not my first rodeo with bikes (20 in as many years) but my first Harley based bike, so I'm totally out of my element here. The thing shakes like a cold, scared chihuahua and has an oil leak from the head but from what I've heard about them that's normal. I can't believe that big bore manufacturers don't have their names on the cylinders, but from my research they don't. On the one hand I want to pull the head and drop a snap gage in the cylinder to be sure, on the other hand I don't want to pull the head without knowing which size gasket to buy for reassembly. Edit: only pic so far is on my phone and it's too big to post. To further add to the confusion it had a k&n filter and trimmed airbox, but still had the crimped clamps on the fuel line. Already ordered a new 'front isolator' from surdyke Harley for $43. (Message edited by Whodat on June 29, 2016) | ||
| Gearheaderiko |
When the kits cost $500-$600, the names were on the cylinders. But when they brought the price down to $300, that changed things. You can also buy just a piston and bore your own cylinder out. It is really only a .060" overbore,which is nothing to be concerned about and doesn't really need special gaskets. Most of the power comes from the piston being 10.5 compression. The 515 kit was a huge waste of money at $500-$600, but at $300, it's not much more money than buying a piston, gaskets and getting your own bore and hone done. It's convenient more than anything. "Big bore" is laughable. | ||
| Gearheaderiko |
They make a 600cc kit. THATS big bore!! | ||
| Whodat |
True. I bored my xr400 to 416 more to fix prior owner's screw ups than anything else, and dropped a high comp piston in at the same time. Extra power was probably there, but not enough to claim as a performance kit. So what do you recommend, stick with the 175 or drop to the 170? I'm by no means looking for power from this bike, just not wanting to seize it by running lean or drown it by running rich. | ||
| Whodat |
Also they make a 1350 kit for my FJ1200, That's a big bore kit! I love me some old air cooled engine. | ||
| Gearheaderiko |
As you know, the higher the number, the richer the jet (in stock CV carbs). 42-45 or 170-175 is not a huge jump. Higher compression should mean you can run a leaner mixture (by matching the piston better to the head, etc.) However, early 515's burned up due to a lean burn situation that was probably more caused by a failure in piston design. So you need to keep an eye on it. Running rich is of course safer. You may not notice the difference between the 170 & 175, but you will notice the difference in 42-45 or shimming the needle. It's all in the time you want to spend tuning it, as to how much you'll get out of it. Just watch for lean! | ||
| Whodat |
Ok, here's the mark.  | ||
| Ezblast |
Usually any mark is at the base of the jug - of course this is a very early niksil jug - one of the first 515cc kits offered - still going strong with no work after using it also on a rebuild, with a new piston and rings! Screw the cheap stuff.  EZ |
