Need recommendations for 680 kit


32 replies to this topic
  • khelton

Posted July 16, 2005 - 10:29 AM

#1

Would appreciate recommendations on piston manufacturer, compression ratio and cam for my beloved XR650R SM. Will the engine live if bumped to 11:1 compression ?

  • Mikie1

Posted July 16, 2005 - 01:34 PM

#2

I'm really happy with mine. Call Luke's Racing- they'll set you up with everything, and it'll actually save money over going direct. www.lukesracing.com. I was in a major hurry for everything-- what they didn't have in stock they had drop-shipped direct to me from the manufacturer or the distributor. Plus, they are just downright honest, up-front nice guys. I'll definitely do business with them again.

My cylinder was done by Millenium Technologies. $160 for the replating and an extra $30 for the over-bore. My 11:1 Wiseco piston was sent to them so they could set the bore to .0025 clearance. Outstanding quality and service. The Wiseco is the only choice for the 680 piston (102.4 mm).

Luke's racing also supplied the Hot Cams Stage II cam. It's made to run with all the stock valvetrain components (rockers and springs), and is a straight bolt-in. No shortening valve guides, retainers, etc. There's no reason to believe this cam won't last as long as the stocker. When I do a tear-down before the Baja 1000 I will probably put in Kibblewhite stainless intake valves, just for a little more durability. The OEM exhausts seem fine.

I run a standard bore Quicksilver carb. I understand you can gain 1 or 2 HP on top with an over-bore carb. You can send it to Edelbrock- they'll bore it for really cheap (something like $40). The stock size works great for me, and there are no flat spots or glitches anywhere in the powerband. I already bump into the rev limiter hard with 15/46 gearing, so I'm not really looking for more top-end.

I've been running a Barnum's pipe, but am experimenting with others. Just got an FMF power bomb header and an e-series ProMeg silencer. Haven't had a chance to ride with this setup yet, but with 12 disks and the block-off plate it's a lot quieter than the Barnums pipe, about equal or maybe a little quieter than the stock pipe/ HRC tip.

I do notice a little more vibration at high revs with this setup. I am still thinking about whether to buy the Falicon crank that's supposedly "dynamically balanced", but they don't do anything with the counter-balancer, so I'm suspicious that this would really do anything. I'd think they'd have to balance the crank/ counterbalancer and rod/ piston all together. Anybody got any other ideas about this??

  • irondude

Posted July 16, 2005 - 01:44 PM

#3

After much trial and error heres the best set up for the XR680R:

1) Ross or Wiesco piston/rings. Cut out piston so it clears valves! (very important) 10.5:1 if you want to get 15,000 miles or 11.25:1 is you want to race it a season or two. Significant difference in power.
2) HD crank with XR600 bearing. Have the crank machine balanced.
3) Kibblwhite blackdiamond valves w/ hd springs and Ti retainers. Dont oversize the valves.
4) Cometic gaskets.
5) Carilo rod.
6) HRC HD cam gear, chain and guards.
7) Hardened rocker arms (for the hotter cam)
8) Stage 2 cam (HRC or Barnumspro or hotcams)

Also:
Edelbrock carb.
Cut out side cover.
Free flow pipe.

Do this and you have the ultimate and it will last a long time.

Engine builders in the order i would choose:
Rob at Barnumspro.com
Eric at Precision Concepts
Steve (?) at Berkely Honda
you might be able to talk Chris Blaise into building you one...
XR's Only also has the ability to do it...

  • irondude

Posted July 16, 2005 - 01:51 PM

#4

[quote name='Mikie1 I'd think they'd have to balance the crank/ counterbalancer and rod/ piston all together. Anybody got any other ideas about this??[/QUOTE']

While the Falicon is a good product - as is the Carilo if you can get one....either way its worth having the crank machine balanced. They weight it all and just shave the crank until its perfectly matched. A must for the 680R and the LC4 KTM for that matter...your crank and your hands will thank you.

  • khelton

Posted July 16, 2005 - 05:37 PM

#5

Many thanks Guys...very helpful. :applause:

  • BWB63

Posted July 16, 2005 - 09:27 PM

#6

102.4 mm Wiesco 11:1 piston, Kimberly White S/S valves (3mm over sized intake), Heavy duty Valve springs, HRC cam chain, Corillo rod, BarnumsPro Cam, Valve stems decked, 42mm over bored Edelbrock.

I wish I would have had the crank machine balanced. It is real smooth but, I hear machine balanced is even smoother.


All About the XR650R Click Here: :applause:

  • khelton

Posted July 17, 2005 - 08:40 AM

#7

All the info and opinions appreciated..if ya got 'em, send 'em..
Tks :applause:

  • Ramcc4x4

Posted July 17, 2005 - 12:03 PM

#8

So what would the cost be for one of the above 680 kits?

  • BWB63

Posted July 17, 2005 - 01:29 PM

#9

So what would the cost be for one of the above 680 kits?



If you are doing the work yourself, http://www.lukesracing.com/ is the way to go. I bet you could even send them the whole thing and it still be cheaper then most places. I just did my sons bike a few months ago through them and then turned Mike1 onto them. Best place I have ever delt with. For the head work and all the parts it's going to be about $1500 for the parts. That is Valves, cam, piston, bore and nikasil, valve job, valve springs, timing chain, gastet set, seals, Now you have to do the work.

I have oversized intake valves and they do not take away from the reliabiltity in anyway, if installed right. They added Horsepower and torque at every part of the power curve on the dyno. The draw back is the next rebiuld I have to replace the valve seats. If I would have gone 1mm oversized instead of 3mm oversized I could have gone up to 3mm on the next rebiuld.

http://www.borynack..../dynocharts.htm

  • Mikie1

Posted July 17, 2005 - 01:35 PM

#10

... Best place I have ever delt with....


DITTO!! :applause:

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • irondude

Posted July 17, 2005 - 02:22 PM

#11

I've only had my XR650/680 engines rebuilt 6 times...so i dont know everything.

BUT--i strongly recommend against building your own XR680R.
Its one thing to rebuild your own OEM Honda. Its easy. Connect the dots.
Add this to that to this to that and it will work fine. Any parts changer can do that.


Try matching all those aftermarket parts together and you are lucky if the motor lasts 50 miles. Theres at least 3 examples of guys trying this on here on TT over the last few years...and they ended in failure.

There are lots of little tricks to get it all to work right. If you think you can just shop out those parts and bolt it all together....consider sending a PM to Johnnyairtime and ask him who is fixing his bike-and why it is being rebuilt for the 3rd time in 18 months!

Those parts DONT bolt up together. About 1/3rd of them need special attention to get them to work with the other aftermarket parts.

Each part will work fine with an otherwise OEM motor. But put any of the two Kibblwhite valves you can go with in any of the 4 different sizes together with a Ross piston--only one of the combo will not hit it in the head...does the kid on the phone at Luke or TT Store or wherever you shop know which one to order? Hell NO! Does Kibblewhite or Ross know which one? Nope!

Cometic gaskets...which size works with the high compression piston? which doesnt? Get it right and you are the power maniac...
Get it wrong and you are done. You think Lukes or even Cometic can tell you what to run with the Carilo rod? of course not.... theres Lots of other examples.

IF you are really going for the whole enchilada...theres only a handfull of people who know what works and what doesnt and it doesnt matter if you are the worlds best wrench...its a matter of trial and error-you have to know this motor-if you want to take it to the edge--reliably.

In Jan 2003 Johnny Cambells bike blew up 25 miles into the Parker 250...it cost Team Honda the number one plate...and it was becouse he didnt get it right. Aftermarket parts didnt go together...
You really think you can do better?

No way.

If you are really going to go for it...do yourself a favor and save yourself a bundle--get an EXPEREINCED XR650R engine builder. Not a parts changer. A real performance engine builder.

  • khelton

Posted July 17, 2005 - 02:40 PM

#12

Irondude..your timing is awfully good..just walked in after trying to bolt on 3 aftermarket parts that should have been a cinch, don't match other stock parts,no joy.

Do you have an engine rebuilder you would recommend ?

What if it is kept simple w/ just 11:1 piston, rings, rebore and chrome ?

  • irondude

Posted July 17, 2005 - 05:54 PM

#13

Engine builders in the order i would choose:
Rob at Barnumspro.com
Eric at Precision Concepts
Steve (?) at Berkely Honda
you might be able to talk Chris Blaise into building you one...
XR's Only also has the ability to do it...




each has strengths and weaknesses....like cost, availability, etc. but for sure each can build the motor right the first time.

as for just putting in a 11:0 piston and rings with the big bore--yes for sure you can just do that...but to really get the most out you need a cam.
in fact i would go for a stage 1 cam before the big bore...you will feel it more.

BUT--if you do both cam and big bore--you really do need to work on the whole thing...cam chain will break (been there) rockers will wear (been there) and the crank will go--especially in Motard. I've seen 5 of these engines puke cranks.

So for what its worth:
stage one-
cam - stage one, pipe, airbox holes, edelbrock carb
(this is the common baja 1000 set up-fast but reliable)

stage two-
above plus 11:0 piston (650)
HRC cam chain
(this is the pro level racer set up)

stage three
above plus 11:0 piston (680)
stage two cam
rod (either one)
crank work (hd bearing and machine balanced)
rocker arm work (welded for hardening-longer lift time=more wear)
valve work (Ti blackdiamond)
(this is what the elite run--only 4 guys know whats in Team Hondas motor--but its very close to this)

of the three options stage two runs a slight risk of the crank going but its only a slight risk...

each set up will be a VERY noticable increase in power. each will last a long time and is a safe way to go. yes i have done each of them as well as other combos...hope that helps.

  • BWB63

Posted July 17, 2005 - 09:11 PM

#14

Straight up Barnum Screwed my engine up the first go round. Second go round I got it back after he rode it from his house to El Mirage dry lake bed and gave it back to me with only half a quart of oil in it. Told me to run the fresh tank of gas through it and I would be ready to go. It was bone dry. It wasn't a good experience. :p :p
In the end I was treated like I did something to him. I was told that he was losing money on my bike, like I was the one that made him put it together wrong. Well I got some grips and some stickers. So, I am real happy and everything is better :eek: There are those That can check tolerances and make sure it will work. Some do the research and find out what works, some take it to someone else that says they have and they can still screw it up. I could go on and on about how screwed up the whole Barnum experience was but, he may do a great, awesome job for the next guy :applause: My bike runs now and I hope it isn't damaged from all the metal that was floating around after the first seizer or the low oil on the second rebuild. Gasket sealer to make the gaskets reusable. :p Powell seems to have done a great job on his 680cc, 11:1, cam, Nikasil rebiuld but, I guess he was just luky. Can't wait to see the Dyno chart for his bike. Ran the Baja 500 without a hicup :)

  • khelton

Posted July 18, 2005 - 03:04 AM

#15

Gentlemen..this has become very educational...no doubt your input has saved me money, major time and major frustration...pls keep the info and opinions coming if you will...Tks

  • Mikie1

Posted July 18, 2005 - 09:40 AM

#16

Nice posts, guys. Irondude, I agree with everything you said, except I think the 680 stage needs to be Stage 3 and Stage 4. I'd call mine Stage 3. Yours and Bruce's bikes are definitely Stage 4.

Bruce, I can't claim the credit for my "luck". My good friend Shawn Black helped me with the rebuild (or maybe I should say I helped him...). We also had help from Sean & Terry Sage, who've had a bike shop for 30 years and have built dozens and dozens (probably hundreds) of race bikes over the years. :)

We did clearance check everything when we put it together, including valve spring coil bind, retainer-to-seal clearance, clay-checking the valve-to-piston clearance, cam timing, etc.

What I found was that the HotCams Stage II cam went together perfectly with the Wiseco 11:1 102.4 mm piston, with no special retainers, shortening valve guides, springs, etc. Clearances were all within recommended specs (though just barely). Shawn has way over 10,000 miles on his HotCams Stage I cam with the stock rockers and valve springs, and the stock cam chain, guides, etc. I spoke with someone at HotCams (wish I could remember his name...). He said they haven't changed the StageII cam since it was put on the market four years ago. He's had the same StageII cam in his 650 ever since-- guesses he has at least 10-15,000 miles on it, and says there's no reason to believe it would be any harder on rockers than the Stage I cam, as long as you stick with the stock valve springs and the stock CDI/ rev-limiter.

As far as the rebore/ re-Nickasil, Millenium Technologies did an outstanding job on the cylinder. The coating is at least three or four times thicker than stock, and there was NO measurable variation in the bore. :eek: The only thing Millenium didn't do was to set the end-gap on the rings.

As far as I know, the Wiseco is the only 102.4 mm off-the-shelf piston available. I went with the 11:1, and haven't had any pinging issues, running straight premium (91 octane) pump gas-- even Pemex. Wiseco also makes their own head gasket set to match this piston, which I recommend. Clay checking the valve pockets, we had right at the recommended valve-to-piston clearance (.070, I think), using OEM valves. The piston would definitely had to have been clearanced with oversize valves, or maybe even aftermarket stock-size valves if they have a thicker face.

I'm sure going with bigger valves, bored carb and a cam with higher lift/ more duration/ steeper ramps, different CDI with a higher rev limit, etc. would produce more power. How MUCH more, I don't know. From everything I learned, the cam profile and the rev limiter are what dictate the extent of the valvetrain mods necessary; increasing the rev limit would require stiffer springs, hardened rockers, extra retainer-to-seal clearance (hence shortened valve guides), etc.

My objective with the valvetrain was to stay as close as possible to stock for the following reasons: #1, it works. According to Bruce Ogilvie and Bob Bell, Team Honda's bikes use only OEM valvetrain components. #2, cost, and #3, from my own experience (though this goes back two decades...), I've seen more failures with welded/ hardfaced rockers and re-ground cams than with billet cams and stock OEM rockers. Barnums, Web Cam and XR's only cams are all re-grinds.

I pre-ran about 600 miles before the race. I checked the valves twice in this time, and again after the race. Since the race, it's done three hard rides, probably another 500 miles total. So far, no problems (though I think the clutch is toast after being PUNISHED on the Tahoe ride last weekend) :p . I imagine the bike will see a couple more Mexico rides and two or three MRANN races before next season.

I am very happy with my current setup, though I do plan on a tear-down and refresh before the 1000. Not looking for more power, but just for my own satisfaction. At that time I will have the Carillo rod installed and the crank balanced (though I am still a little suspicous... :applause: ), put in new crank and counterbalancer bearings and the HRC cam chain/ sprockets/ guides. None of this requires a rocket scientist to do, though if you have to refer to the manual to set your valve clearance this is probably something better left to someone with more experience. If you do things carefully, methodically and check and re-check all critical clearances, you will be fine doing it yourself. If you plan on changing your CDI/ rev limiter, going with a cam with higher-lift/ more duration than a HotCams Stage II, and/ or bigger valves, you would be better off having someone with more experience do it for you. Hope this helps...

  • roadcam

Posted July 18, 2005 - 10:59 AM

#17

I don't know how many riders consider this, but ... you buy a Honda for the reliability and longevity .. you can modify anything, but you can't replace dependability ... as much as I hate to say it, if you're looking at strictly performance, and don't mind frequent maintenance and replacing parts $$$, ... why not just get a KTM, or Yamaha, (God, I hate those words) .. gotta go wash my mouth out with Honda 4-stroke oil now ... :applause:

  • magilla

Posted July 18, 2005 - 11:43 AM

#18

To provide a counter-point to Borynacks experience, and to back up Irondudes recomendation...

Rob Barnum built my XR680RR engine in my Motard and it's an absolute freight train. Good people, honest and pleasant to deal with. Definetly went the extra mile to make it all perfect. The various options have been covered pretty well already, lets just say mines got everything listed here and then some. No dyno yet, but it pulls dead even with a 2005 Yamaha R1 up to 115mph when it bounces off the 9k rpm rev limiter in 5th. (15/45)

Can a thoughtful, experienced amatuer put one of these together? Maybe, but I'd send my engine to Rob again in a heartbeat. :eek:

In hindsight I could have just bought a Husaburg... But it wouldn't be my Honda. :applause:

  • neduro

Posted September 21, 2005 - 11:58 AM

#19

This is exactly the data I was looking for.

I just bought an 02 with a munched engine (bottom end failure, lots of bronze swarf floating around, was shut down pretty quickly) and am debating rebuild options. I tore the top end off Monday night with the previous owner, and we got far enough to determine that there's nothing wrong up there.

I'd like to build it back up to run a bit stronger than stock- most of my riding is at 8000 feet or more, and the stock motor is a bit underwhelming up here. However, I also ride in Baja and low elevations enough that it's important to me that the motor is A) reliable and :banghead: able to run on Pemex.

I'm in a rush, as I want to use this bike for prerunning the 1000 this year.

I think I've narrrowed it down to 2 likely options.

1) Send it to Rob Barnum to become a 680. Downside is that the schedule is very tight between shipping the motor, dealing with parts, etc. Upside is that Rob is a very nice guy, I've heard a lot of good things about his work, and he knows the motor inside and out. And I'm sure it'll be faster than I have any use for when I get it back, which sounds fun.

2) Turn it over to a local motor guy (Jay @ barebones.net) and keep it a 650 w/ 11:1 Wiseco and a Stage 1 hotcam or the like. Cheaper, he's local so the schedule and logistics are easier, and his reputation is outstanding. But, he hasn't done much with the 650R motor (he does have a ton of experience working with the air cooled RFVC plant) and I'm not sure what else to recommend beyond piston and cam.

I would very much appreciate all thoughts and comments. Motor is sitting in a box, ready to ship, and is either going to Jay or to Rob tomorrow- if I want it back in late October, time is tight as it is.

:ear

  • neduro

Posted September 28, 2005 - 06:07 PM

#20

Motor went to Jay, has been torn down, and parts ordered. Verdict, according to Jay, is an improperly installed crankshaft from the factory. More details once I see it and talk to him further. Top end looks perfect, no damage to transmission, so it's basically a crank and that's it.

Decided to go mildish on the build- 11:1 wiseco in the stock bore, and hotcams stage 1. Hopefully it will run a little stronger without turning into a grenade.





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