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Cam choice.

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ReggieV View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ReggieV Quote  Post ReplyReply Direct Link To This Post Topic: Cam choice.
    Posted: 25 Jan 2016 at 18:42
I'm going to get a more sporty cam for my 950 which is getting soon, high (...er than standard) compression pistons.
 
I'm not trying to build a racer, and still want good mid-range power and reliability.
So the choices are;
The B10 was a factory spec cam, and as far as I know, with no known reliability issues.
The there's the P3.
Followed by the SS2 which has more lift and overlap apparently giving good mid-range and a better top end. 
 
From personal experience, can anybody give me any feedback/issues on any of these cams and opinions?
 
I'm sure that none of them will disappoint, but I'm wondering whether to go mildly tuned, B10 or slightly more radical with the P3 or SS2.
 
Thanks in advance,
 
Reggie
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Post Options Post Options   Thanks (0) Thanks(0)   Quote LarsW Quote  Post ReplyReply Direct Link To This Post Posted: 26 Jan 2016 at 08:28
Get the engine blueprinted, lightened and balanced. Then you will have most gain from these cams. 
I have run B10 and P3 in quite standard LM3-engine and not noticed much difference, but the bike was not properly tuned on a dyno.

On the other hand, I once purchased a really good set up (totally reworked) LM3 with a P3 cam, so if done right you can get good results with it. Not shure about the reliability issue, though.

Have you looked at the products from dynotec.de ?

Ciao,
Lars W
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dukedesmo Quote  Post ReplyReply Direct Link To This Post Posted: 26 Jan 2016 at 13:32
My LM2 had a B10 cam and high comp pistons, it went well but my first proper ride saw a piston to exhaust valve collision, probably caused by a combination of things (35 yr old valve springs?) but it may have been 'safer' without?

I have since rebuilt with 950cc pistons but have not run it yet. I'm not really after big power though as it's an old bike and never going to be as fast as my other bikes, I just want reliable and reasonable performance.

Le Mans 2
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Post Options Post Options   Thanks (0) Thanks(0)   Quote dan_s Quote  Post ReplyReply Direct Link To This Post Posted: 30 Jan 2016 at 15:55
LM 1-3 came with the standard cams,the same as in the T3, sp1000 and G5 . V1000 LM's came with the B10 which is mildly higher and will fit straight in the lm 1-3. Mgcycle in the US sell cams reground to B10 specs. Another drop in cam is the 620x9 from megacycle.
Then there are the 620x10 cam which requires recesses for the valves in the piston and wackier race cams.
All recommend new or as new tappets and careful running in. Some cams require stiffer springs.
Ed Milich who races guzzis wrote me that no straight drop in cam is worth the hassle.
HMB guzzi in Germany sell cams and springs sets but I haven't heard opinions on these.

Edited by dan_s - 30 Jan 2016 at 15:58
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ReggieV View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ReggieV Quote  Post ReplyReply Direct Link To This Post Posted: 30 Jan 2016 at 16:54
Thanks for the replies.
I looked on the MGOC forum a few days ago and Chris gates01264, was asking a similar question and found out that now Raceco have stopped trading there are options such as going directly to Gutsibits for a P3 at about £400 or Motomecca will regrind a B10 for about £265, but Chris found that "Kent cams" used to grind the camshafts for Raceco and have all the grinds on file including the B10, P3, SS2 and can grind a cam for 130 plus vat!
 
I've also emailed HMB Guzzi in Germany, and their brief reply to me said that as I elected to do the work myself, I would have to send the heads, barrels and pistons and the cam to them to set up / machine etc etc and they would return it all ready to fit for about £1,000. So this would have probably new valves, springs machined pistons.
They also have a chart showing various configurations and the alleged BHP that you get.
 
dan_s wrote;Ed Milich who races guzzis wrote me that no straight drop in cam is worth the hassle.
 
That made me laughLOLLOL
 
Decisions, decisionsConfused
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gates01264 Quote  Post ReplyReply Direct Link To This Post Posted: 09 Apr 2016 at 20:46
By the way the Kent cam re-grind was £130 including VAT , in the end I sent my old worn cam to Kent cams for a re-grind to B10 spec, they said that it could be re-ground without the need for re-hardening, however the fact that my original cam was worn out of specification suggests to me that the case hardening has gone! So I ended up getting the cam back off them. After MUCH research I went for the HMB 8.1 cam kit which uses the original guzzi 0.22mm valve clearance and complements my 88mm (950) conversion, the cam is also a much better design because of the oil lubricating holes being ON the cam lobe instead of next to it ensuring a constant oil film between the tappet and the cam lobe, the cam is also plasma nitrate hardened and re machined to a very high standard, when you use the springs in the kit and shimmed to the spec given it can be installed without modifying any of the engines internals. HMB also gave me all the jetting info for my set up. I have installed the kit but yet to fire it up, so fingers crossed!!
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ReggieV View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ReggieV Quote  Post ReplyReply Direct Link To This Post Posted: 11 Apr 2016 at 13:35

Hi Chris, how did you come to the decision to get  the HMB 8.1 cam? I've looked in the site and see it says suitable for the 950 stating;

"Torque Kit for significantly more power at low and medium revs as well as up to 9 PS increase for the models Le Mans 1-3 und all touring models with 36 mm carburettors."

Was this recommended by HMB and are there any comparisons to other cams such as the P3, SS2 etc?
 
I have to confess that other motorcycle related issues have temporarily stopped me with my Guzzi engine build although I have bought a new pair of Nikasil 950 barrels in preparation. In my post above yours I notice that I've written that I'd "emailed HMB in Germany" when in fact it was Dynotech in Germany. (Old age is catching up with my brain!)
 
I'll be interested to know how well it goes when it's done. I will be doing mine probably later this year as I'm retiring very soon so should have more time.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote red leader one Quote  Post ReplyReply Direct Link To This Post Posted: 11 Apr 2016 at 13:39
I think you  find that you won't have more time.

You will find that you will be wondering how you found time to go to work.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gates01264 Quote  Post ReplyReply Direct Link To This Post Posted: 11 Apr 2016 at 15:03
There are a number of factors that influenced the decision on the HMB 8.1 cam, I did an awful amount of ringing about and research, at the beginning I wanted a B10 cam but they are totally unobtainable and I didn't want to install a second hand one after spending thousands fitting new parts to the engine (all the second hand B10 cams I managed to track down were worn), I then looked at the RACECO ss2 cam/spring kit but they are no longer trading so no luck there, Then I contacted megacycle but found them unhelpful and I have read about quality/hardening issues with their cams, so I took a look at Gutsibits P3 cam which is made in Italy with a six week wait, but it didn't inspire confidence as they didn't have any specs or info on the P3's manufacture other than "its a good cam", when going to this level of cam duration/lift it is a good idea to change the valve springs (as stated in guzziology and by others in the cam tuning world) to suit the cam and Gutsibits didn't offer this.
one of the biggest problems with remanufactured cams is the quality, I have read about so many new cams scrubbing out due to hardness issues, I took a look at the HMB site and contacted him about the cams he offers and unlike others he has a real understanding of cam design and the engineering/technical processes and can explain why they have done what they have with the cams, they have also sold over 100 of the 8.1 cams with apparently no problems and there own test bike has done silly miles running this cam with no issues, so it is a proven cam with mods ie the lubrication holes on the lobes and cam lobe design to help the drivetrain, including the prevention of burning the valve seats. 
I just wanted a cam that complements my 950 conversion and not a race bike style of tuning, also I wanted a "drop in cam kit" as I didn't want to get into machining the engines internals (this gets very complex) and the 8.1 cam kit seems to fit the bill, plus its German quality.
The proof is in the pudding as they say, so ill let you know how I get on.


Edited by gates01264 - 11 Apr 2016 at 15:40
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ReggieV View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote ReggieV Quote  Post ReplyReply Direct Link To This Post Posted: 11 Apr 2016 at 16:04
Hi Chris, thanks for the very informative reply.
I did ring Kent camshafts in January and wasn't overly inspired with confidence when I spoke to the relevant chap about re-profiling my existing camshaft, and then as I said, I emailed Dynotech who replied in a slightly odd way.
 
They added comments at the end of each of my points/intentions which were brief, and on a couple where they (I assume) didn't agree with my intended fitment of something such as where I said I was considering putting a RAM clutch on they just added "bullsh*t" underneath without suggesting their preference. I don't doubt that they can do a great job with an engine but they didn't come over as really easy to deal with. Maybe they get a lot of time wasting emails and don't waste too much of their time replying.
 
Based on what you've said Chris, it sounds as if you've taken a good route and if the engine is improved as it suggests it should as you say, coupled with German engineering be a good move. Again thanks for taking the time to reply to me.
 
Martin


Edited by ReggieV - 11 Apr 2016 at 16:07
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gates01264 Quote  Post ReplyReply Direct Link To This Post Posted: 11 Apr 2016 at 18:21
No problem martin,
I had the same experience with dynotech, Also their cam kit was about 260 euros more expensive than the HMB kit, I have a feeling that the HMB kit and Dynotech kit are the same as they are both re-grinds of your original cam, the write up and appearance of the kits are pretty much identical, both the company's kits are plasma nitrate hardened, also they are both German dealers so probably use the same parts suppliers and specialist machinists. Cheers, Chris.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote jehu Quote  Post ReplyReply Direct Link To This Post Posted: 22 Jul 2016 at 15:20
Is your bike running now?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gates01264 Quote  Post ReplyReply Direct Link To This Post Posted: 22 Jul 2016 at 22:15
Hi, yes it's running very well and im very happy with the end result even though i haven't done many miles this year due to the constant bad weather and my other guzzies needing attention ☹️

Edited by gates01264 - 23 Jul 2016 at 10:23
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