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SuzukiSavage.com
/cgi-bin/YaBB.pl General Category >> Rubber Side Down! >> Valve job /cgi-bin/YaBB.pl?num=1375947497 Message started by mpescatori on 08/08/13 at 00:38:17 |
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Title: Valve job Post by mpescatori on 08/08/13 at 00:38:17 OK, so let's assume I am ready for the next winter project... a valve job. As we all know, the Savage head is a 4 valve head... too bad for the undersize valves... :-[ So... I would like to ask "those in the know" ;) what size / code valves are the Savage's stock valves, and how much wider can we grind the valve head seats ? I honestly see little point in fitting a "hot" cam on... "cold" valves... ::) |
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Title: Re: Valve job Post by Dave on 08/08/13 at 03:42:58 From what I saw when I was in there.......there is little reason to put in bigger valves as the exhaust ports are very limited in what can be done. There is a weird square hump that protrudes down into the exhuast port, and it is the bottom of the valve spring pocket. You can open up the ring at the exit of the exhaust port, clean up the castings a bit in the ports, and button everything up. I don't konw of anyone that makes a "hot" cam for this bike - the 3 available cam grinds are all increasing stages of "mildness". The Stage 1 cam is what I installed and it runs great and does provide a power boost. The Stage 2 cam is a bit hotter but still not a race cam and is very streetable. The Stage 3 cam is between the Stage 1 and Stage 2. Do your valves, add a cam, put in a Wiseco, change the carb to a Mikuni VM36, add a free flowing exhaust.....and you have all the motor that the clutch, chassis and brakes can handle. |
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Title: Re: Valve job Post by mpescatori on 08/08/13 at 04:50:05 Hi Dave, thanks for the input. I have a Stage3 cam from lancer - but I will not put that in until I can have a proper I have two carbs on hand, one is the OEM carb wghich was cleaned up and tuned courtesy of Lancer 8-) the other is a Mikuni BST40 also "hmmm'd" "oooh'd"and "aaah'd" by Lancer ;) I have a 5"dia x 2" thick K&N air filter with 2" dia. plumbing to the carb, already running. A little hesitation when cold under 3000 rpm, but once warm it's a beauty. The point is the engine will rev and pull like a banshee from 3000 to 5000. I believe she (and I) is entitled to revving to 6000 - if not a little more. Also, I can scrape the pegs and keep up with the 300-400cc scooters, but Silverwings and TMaxes... :P Still... overtaking WideGlide Harleys on the outside and revving away ... priceless ! |
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Title: Re: Valve job Post by LANCER on 08/08/13 at 04:51:34 DR650 available cam profiles listed on the WebCam site are considerably higher than what we have now, but then the DR exhaust ports a MUCH nicer that ours. Valve sizes are the same. This is for the 90-95 models. Lift: .390/.380 Duration @ 0.050": 248/248 Lift: .417/.405 Duration @ 0.050": 254/254 **************************************************** Numbers for the LS650 CAMSHAFT VALVE LIFT IN/EX DURATION @ .050 Stock camshaft .254/.244 224 Webcam std. .256/.256 226 Stage 1 .264/.264 239 Stage 2 .274/.274 248 Stage 3 .273/.273 238 Effects of duration: 220-235 => Low End Torque 235-250 => Midrange Torque 260 + => Top End Power |
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Title: Re: Valve job Post by mpescatori on 08/08/13 at 04:55:21 Hello Lancer, thanks for the info ! Does this mean I can/ should leave the valves as is, and only work on intake/exhaust ports? (and fit your cam, natch... ;)) |
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Title: Re: Valve job Post by Dave on 08/08/13 at 05:04:35 My engine has a Stage 1 cam, Wiseco 95mm, Mikuni VM36....and it easily revs over 6500. My Trailtech Vapor claimed that once I did 7,200 rpm. I found that my stock carb had a flat spot as you are describing, and the cure for me was to raise the slide needle a bit. I had removed the white spacer and installed 3 of the metal washers. I tried bumping up the pilot jet to cure the lean spot....but it did not help. I had an oxygen sensor and meter installed, and the trick was to remove one of the washers to allow the needle to be raised, then I dropped the pilot jet back down to a #50. It then ran great with a #50 pilot, #150 main and 2 washers on the needle instead of the white spacer. |
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Title: Re: Valve job Post by mpescatori on 08/08/13 at 05:17:30 78434E5948445F59424A47582B0 wrote:
:o ... which is exactly what I had in mind ... I will consider the "2 washers on the needle" and verify I have a #50 pilot; I'm quite happy with my main (I think it could actually be a #147.5 ...) 8-) Thank you ! |
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Title: Re: Valve job Post by LANCER on 08/08/13 at 08:29:14 263B2E38282A3F2439224B0 wrote:
The valves themselves...yes, leave as is; unless the engine has a good bit of mileage on it, and if so, then a good basic valve job to insure proper sealing is all that is needed. I do like to clean up the exhaust ports, but thats just me. The crocked path and the exit ring that Suzuki deliberately designed to make this a low power engine just really bothers me. I think they simply did not want another 650 single engine to interfere with the DR's role in their lineup. The intake ports don't need any work, they are good as is. If you want to get picky about though there is one thing that can be done that is considered to be helpful in improving air flow, and that is to polish the inside corner just under the valve seats. As the air flows in through the intake ports, it turns upward toward the valves, and it is the inside corner of that path which is polished. Along with & part of that path is the bottom edge of the valve seat. If that edge is not smooth with the aluminum of the port wall, then mechanical smoothing of it will remove that small "speed bump" from the air pathway and should result in better flow. When doing head work I use "touch" as a guide to what needs to be smoothed. There are the basics, like doing the inside corners, but from there I feel my way through and if I feel something in the way then it is removed or smoothed. These are the small things that interfere with flow; the big things, like the outer ring, just need to go. It's like on a fighter aircraft; they originally had standard raised rivets until it was discovered that flush rivets reduced drag and allowed the aircraft to perform better. Airflow is airflow. |
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Title: Re: Valve job Post by paulmarshall on 08/08/13 at 12:36:42 Bike builder Dave Degens claims smaller valves produce more power at the rear wheel. His story is about half way through. http://www.youtube.com/watch?v=jy95JWtWNbE |
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Title: Re: Valve job Post by ralfyguy on 08/08/13 at 15:54:39 I'm thinking about smoothing out the exhaust port for some time. But I want to keep the stock header. Would that do any good or would it even do harm? |
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Title: Re: Valve job Post by Dave on 08/08/13 at 17:53:53 50434E445B45575B220 wrote:
I am using the stock header and I have made a lot of modifications....one of which was doing some porting work that included reducing the size of that ring. Removing the ring alone won't make a big difference.....but taking a bit of it out won't hurt anything. |
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Title: Re: Valve job Post by paulmarshall on 08/08/13 at 18:28:28 79424F5849455E58434B46592A0 wrote:
I am using the stock header and I have made a lot of modifications....one of which was doing some porting work that included reducing the size of that ring. Removing the ring alone won't make a big difference.....but taking a bit of it out won't hurt anything.[/quote] Dave you need to get rid of the stock header. It will sound so much better. That was my first mod and noticed more power. |
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Title: Re: Valve job Post by Dave on 08/09/13 at 04:53:16 I plan on making a 1.5" diameter header next winter. Last winter was the Cafe' conversion and it had to be done before the riding season. This winter will be the paint, front fender, and maybe the new stainless header. |
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Title: Re: Valve job Post by Dancomer on 08/09/13 at 13:34:57 very interesting information here, i have alot to think about |
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Title: Re: Valve job Post by justin_o_guy2 on 08/09/13 at 16:26:10 Spend some time reading about intake manifold texture. POlished, low turbulence, supposedly allows the fuel to fall out of the mix, Matching port sizes where trhings bolt up is a good deal, but, when rubber tubes on stobs are part of the game, its not really possible. Maybe smoothing /tapering the ID of the intake manifold where the rubber goes on would help keep the velocity up, but a polished intake on a carbureted engine may not be best. Exhaust? Smooth away,, |
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Title: Re: Valve job Post by LANCER on 08/09/13 at 18:26:23 7E6167607D7A4B7B4B73616D26140 wrote:
Did not say to polish the intake, but "just" the inside corner just below the valve seat. The rest of the intake I leave as is for the reason you mentioned, the rougher surface helps to keep the fuel from collecting on the intake walls, which it will tend to do if those walls are too smooth. |
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Title: Re: Valve job Post by WD on 08/09/13 at 18:51:02 If it is handy, toss up a pic of the exhaust port hogged out, can't find it. Pipe is still off, so ought as well take care of it while the bike is apart. Just one of several topics the search function isn't giving me... |
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