| Author | Message | ||
     Rhpaw |
So, I'm getting into the head this winter -a few days actually- and i'm wondering how does the 515 kit kit FEEL compared to a normal 'piped and intaked' 12k mile blaster? You guys always always talk about ported heads with cams and various other mods, but I'm probably not going that far with this blast. With a stock head, a V&H pipe, a K&N and 170/45 jetting.. a little kick? smoother delivery? Overall, is it worth the $299 if I'm already in there? I mean hell, "While I'm in there!!" thx! | ||
| Ezblast |
Better gas mileage,and it gives everything a bit more kick! EZ | ||
| Reuel |
It's worth it! Higher compression yields better gas mileage and more power. Oh--Ed already said that, huh? I should avoid posting under the influence, huh? PUI! | ||
| Rhpaw |
^^^ thx, that's exactly what I needed to hear. ^^^ drinks on me.  | ||
| Rhpaw |
oh, any issues with jetting? -i'm in Denver- | ||
| Ezblast |
Jet her back to stock42/165 but leave shimmed - that should work for any 515 kit, but if your going with a generic hi comp piston, and sleeve re-bore - then 45/175 would be safe. EZ | ||
| Rhpaw |
Nah, I'd do the standard Nallin kit. Nothing fancy. | ||
| Gearheaderiko |
Leaner jetting may be good for Denver, but I wouldnt necessarily expect the jetting to go leaner just because of the 'big bore' kit w/ 10.5:1 piston. It may stay the same. What I'm saying is use caution going leaner and spend the time to tune it. | ||
| Ezblast |
the 515 kits have been notably leaner in their tuning - but rich is safer than too lean when dialing in a bike's motor. EZ | ||
| Gearheaderiko |
True, but that has not been my experience (on a dyno, FWIW). | ||
| Rhpaw |
Roger that. I'll pay attention to a/f when I getting it back together. Heck, I am pretty lucky that NRHS is 50 miles north. I'm sure if I run into any dial in issues, they'll be able to look at it first hand. | ||
| Vmod32 |
Hi long time reader here, never needed to post before, always found what I needed by reading. However, not so lucky this time. I'm trying to install a NRHS 515 Big Bore kit and I've run into a problem. The push rods are too long, by about 1/4 of an inch. Did I do something wrong or do I need adjustable push rods. From what I've read I should not. All of the valves, rockers and such are stock. I do realize one is longer than the other, but that's not the problem. I've double and triple checked that the engine in on the firing cycle so that both valves are closed. I'm at a loss on why the push rods are too long. Any help would be much appreciated. otherwise I guess it's going to be another week or so of down time while I wait for adjustable push rods  | ||
| Gearheaderiko |
You should not need different length pushrods (so dont buy any). There is a problem and it needs to be fixed as everything should be (almost) exactly the same except the cylinder bore. If you use different pushrods you will undoubtedly have another problem. Although it seems you've checked everything, lets make sure: Have the lifters have bled down? Pushrods are correctly installed-as in fitting in the rocker arms correctly. If they are a little off and you've cranked everything down, they may not be able to slide into correct position. You didnt pull the cams out? Or the lifters? It would concern me that they gave you by mistake a cylinder that had been decked/machined (or just plain wrong). FWIW. If you've followed the CAM installation thread you'll know there are 2 of us on this board that have had failure with the 515 pistons. I'm hoping you checked everything out thoroughly before and during installation. Make sure everything is lubricated well, before starting. Do the recommended heat cycles. Do a compression test, before starting and as often as possible after that until its broken in (appx 500 miles). If you do have a problem you'll know when it started and for how long. Pay attention to any signs of 'knock and ping' and close attention to the A/F mixture. (avoid pulling the spark plug out of a hot engine, and use antiseize on the threads.) | ||
| Gearheaderiko |
http://www.badweatherbikers.com/buell/messages/201 64/280643.html?1245907411 | ||
| Gearheaderiko |
PS Welcome! | ||
| Ylwblast03 |
To me, it sounds like the 515 kits are a bunch of trouble. I'm looking to add a high compression piston and a mild cam (B50), but i really don't want to go with the 515 after reading some of the comments on them. Can I bore out the stock cylinder to accept the large size piston, or is there not enough material? Is it even worth it or would just a stock size 10.5 piston give me just about as much power? I'd really rather not spend extra money for no reason. THANKS!  | ||
| Gearheaderiko |
10.5:1 pistons are available in overbore sizes in .015" or .010" and multiples thereof (depending on manufacturer). I havent had any problems with the .015" overbore pistons. The 515 kit piston is really only a .063" overbore piston and using round numbers the 515 is only 3% bigger than stock. More displacement = more power (in simple terms), but I dont consider the price or risk of the 515 to be worth such a small amount of power. The stock cylinder can actually be bored out .063" too. Buy a .015 over 10.5:1 piston then take the piston and cylinder to a machine shop and have them matched. My opinion is t | ||
| Ylwblast03 |
Sounds good to me - thanks for the info | ||
| Ezblast |
I would recommend the Revolution Kits, with Wisco Pistons, not the CP, as is in the NHRS kits, and enjoy a warranty on the parts as well. EZ | ||
| Gearheaderiko |
Revolution was using CP pistons and if they are now using Wiseco that would be good news, hopefully (I never saw a Wiseco listing for the pistons, but that doesnt mean they dont exist- the Buell stuff was hard to find on their site anyway). I've been meaning to call Revolution about the 600 anyway...... | ||
| Ezblast |
http://www.revperf.com/Blast/BlastPistonKits.html  EZ | ||
| Styxnpicks |
so... I'm just gonna do it. what cam would match a 515 kit with stage 3 xb heads? I'm doing ALOT of highway driving now to work and back and would love to be able to drop down a gear and GO when i need to.. I've also had sportbike guys tell me I'm I pretty aggressive driver >.> thinking the N9 would put down good hp numbers... but one of the red shift cams might suit me better. i figure while i have the bike stripped to the frame might as well get something done.... dark side here I come (Message edited by styxnpicks on October 28, 2009) | ||
| Ezblast |
Red Shift 580 was the recommendation from Terry Parsley. EZ | ||
| Gearheaderiko |
Since I dont have an answer yet (Rev perf site lists CP, JE & Wiseco for pistons), I'd be real cautious about using the 515. Ask questions. It should be noted that the more radical cam you use, the more running/tuning problems you'll have. Awesome peak HP is great, but if you're only getting 30mpg and its a bear to start and run at lower rpms, then it may get less enjoyable to ride. The XB head with stock XB cams will still give you quite a nice punch. If you have the ability to pull the case apart, I'd do the 600. More power with less cam. Sorry, I'm just feeding the dark side... | ||
| Ezblast |
lol - for a more gentle aproach - which is what I'm going to go with is adding ratio rocker arms - the 1.725's - to the existing cams, thus keeping the gentler ramps, however, increasing the breathing. clearancing the valvecover will be nescessary, and adjustable pushrods, etc. as well, still it would better promote longevity and ride-ability vs the more radical cams. Thats the reason they became very popular with the VW Bug crowd. EZ | ||
| The4ork |
im not sure if this has been covered before but ive never seen it... i know you can upgrade to a XB head, but can you upgrade to an xb9/12 or earlier tuber cylinder and piston? im not sure if the cyclinder would even bolt together, let alone if the rod would mate with the piston, or if the tuber/xb rod would mate the blast crank? was just brainstorming :P | ||
| Styxnpicks |
from what ive been reading the xb heads are the same for the 9 and 12. the crank has a longer stroke for the 12 and the piston for the 12 if I remember right is flat or had less dome than the 9 to lower the compression ratio some.. but from what Ive read the heads and cylinder case are the same | ||
| Gearheaderiko |
Styxnpix is correct! You can also bolt just about any "Evo' Buell/Sportster cylinder and head up to the Blast engine, you just need to match the right piston to it (some machining may be required). However, most anything before the XB would be the same or worse performing than the Blast head although some combinations seem promising and some Screamin Eagle heads may also perform better than the Blast head. But the XB head, out of the box, is already suited to high performance in stock form with stock valves and springs that will run to 7500 rpm and use the B70's (almost) equivalent XB stock cams. The XB head also has a superior combustion chamber yielding better mpg! The XB head stuff is no more expensive and seem to be found cheaper than anything else. (frankly XB valves and springs are dirt cheap). Concur with the ratio rockers! I theorize that the B50's cams with the ratio rockers might put out almost as much peak HP as the XB cams but with a wider power band. Haven't had the chance to test it though. | ||
| The4ork |
im in the process of upgrading my tuber with XB12 cylinders/pistons with nhrs stg3 heads. gonna sell the original tuber parts on ebay, and i figure with the $ i'd get out of that id put into the blast. i was just wondering what about the tuber piston/cyl on the blast with the blast head? if not maybe i'll just upgrade the cam and call it a day | ||
| Gearheaderiko |
Not worth the trouble. Little to gain if any at all and you'd be throwing on used parts. What benefits the tuber, benefits the Blast. |
