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Discussion Starter · #1 · (Edited)
i am a noob here, and everything i have learned about my bike i either learned here or from friends. i am about 4,000 miles away from the 12k service, (and will only take a few months to get there now that i am fully recovered from back surgery!) and was thinking about dropping in hotter cams when i did the 12k service.

i am somewhat competent when it comes to basic maintenance and repairing my bike (replaced clutch springs, brake pads, master cylinder, front wheel axle, have removed, rejetted and disassembled stock carbs a bunch, adjusted float bowls, removed AI and airbox, etc) but havent really ever tackled anything "major" yet like the 12k service, but i want to take the next step, and also learn more about my bike in the process, as i hae found that every project so far has allowed me to gain more knowledge (and more tools too instead of giving the dealer my money!)

what do i need to know about doing this that is diffrent from the regular valve check with the stock cams once i drop in the new cams? i have never done anything like this before, but want to do it myself to learn and get the experience.
 

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make sure you have the pistons at tdc and the old cams lined up by the marks before you remove them.Dont turn motor over till you get the new cams in.Then its just a mater of getting the shims right.get a manual before you try it.As long as you stay with a cam that you dont need to cut pistons for clearance you will be fine.I think the tpusa813 is the best cam out there for what you are doing.
 

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Discussion Starter · #4 ·
rmak-

i free'd up some space in the inbox!
 

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Discussion Starter · #5 · (Edited)
make sure you have the pistons at tdc and the old cams lined up by the marks before you remove them.Dont turn motor over till you get the new cams in.Then its just a mater of getting the shims right.get a manual before you try it.As long as you stay with a cam that you dont need to cut pistons for clearance you will be fine.I think the tpusa813 is the best cam out there for what you are doing.
i understand what TDC is and if i get the bike set at TDC (and i am guessing this can be done by putting the bike on a rear swingarm stand or motorcycle jack) and rotating the rear wheel until it's at TDC and this eliminates the need to remove the alterrnator cover, remove the old cams (you have to send them in as a core), get the new cams (which are just someone elses old cams that have a different grind, so i am paying for the grind, not a "new" cam, right") and install them and since they are off of another 865 twin the marks to line it uo for TDC when installing them should be identical, right? then after i install the cams i need to check the clearances on the new cams and if any of them are out of spec, then adjust accordingly with shims. and i have a Haynes manual!

i am guessing these are the tools i will need:
torque wrench
torx and allen head sockets
Triumph anti-backlash tool or homemade equivilant
feeler gauges
calipers (to measure shims if size in unable to read/worn off)
calculator

so just to make sure i understand (and bear with me because this may sound like common sense to a lot of you but this is something i have never done before) the main points here are to:

1. make sure bike is at TDC before removing old cams.
2.remove old cams, send them away, receive new cams. while you are waiting for new cams DO NOT rotate back wheel or move bike. cover up all exposed areas of bike/holes where things may fall into.
3. receive & install new cams in the same position as old cams were, making sure timing marks line up and bike is at TDC.
4. once NEW cams are installed, perform valve clearance check, measuring between valve and shim (feeler gauges for this?)
5. do the math, determine the proper shim size you will need, do the math again just to make sure, drive to the dealer and get new shims if needed.
6. remove cams, replace shims that need to be replaced, reinstall cams (TDC!!!), oil lines, replace cover, torque to specs, and then you're done?
 

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Not to sound stupid, but what is the reason/advantage of replacing the cams? I have my 12k soon and am just curious. I just don't understand the reasoning.
Thanks,
David
 

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dseely1 and Simpson

In answer to your questions.....

Better cams = increased performance

There's a few links contained in this post which may be of interest:-

http://www.triumphrat.net/1149123-post10.html

There are also numerous other threads which can be found using the search function.

Its all very interesting stuff if your inclined toward modding, improving and increasing what we are given as stock.

If you're not, then its not!!




V.
 

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I put a set of 813 cams in my thrux and picked up 10 RWHP. We did the swap at the shop one day and ran back to back dynos, a lot of jetting was needed and it took use about 6 runs on the dyno but ended up with a huge gain. They work very well and can still be used with the stock 25mm shims and valve train. My thrux has 42 Mikunis, Preds and TPUSA air box kit. Ports cleaned up and matched and 865 cc forged 11-1 pistons. These cams really woke the bike up, and have much better lift and duration numbers than the early mystical 790 cams everyone seems to be trying to find. Can't give you the actual numbers but Carlos will be happy to talk to you about these cams.
 

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The cams that come in these bikes are very mild (made that way to pass epa std.)They have made them even milder as the years went by the 01 790 motors had the best stock cams.The later model 790 cams are the next best stock cams then the 865 cams are the worst.
 

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I put a set of 813 cams in my thrux and picked up 10 RWHP. We did the swap at the shop one day and ran back to back dynos, a lot of jetting was needed and it took use about 6 runs on the dyno but ended up with a huge gain. They work very well and can still be used with the stock 25mm shims and valve train. My thrux has 42 Mikunis, Preds and TPUSA air box kit. Ports cleaned up and matched and 865 cc forged 11-1 pistons. These cams really woke the bike up, and have much better lift and duration numbers than the early mystical 790 cams everyone seems to be trying to find. Can't give you the actual numbers but Carlos will be happy to talk to you about these cams.
+1 VERY TRUE they are better then the 01 cams.Ad john said cant tell you the specs but there better.I have checked them.Call carlos if you want cams.
 

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+1 VERY TRUE they are better then the 01 cams.As john said cant tell you the specs but there better.I have checked them.
Did you have to learn the secret 813 cam society handshake and get the club tattoo before being allowed to divulge you own them? I'm completely baffled why the cam specs are held so closely on these suckers and why one needs to buy them before finding out what I just bought!

Yours and ton-ups referral are a step in the right direction, but I don't wipe my ass with $100 bills....so forgive my skepticism!

Cheers,

--Rich
 

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Did you have to learn the secret 813 cam society handshake and get the club tattoo before being allowed to divulge you own them? I'm completely baffled why the cam specs are held so closely on these suckers and why one needs to buy them before finding out what I just bought!

Yours and ton-ups referral are a step in the right direction, but I don't wipe my ass with $100 bills....so forgive my skepticism!

Cheers,

--Rich
Rich, there are countless things we lay money out for without knowing exactly why they work. Medicines come to mind. I'm guessing these cam grinds are what they used to call in my day "trade secrets" or information the manufacturers like to keep close to their chest so every other machine shop can't start making them. I figure these guys spent the time, money and effort to do the R & D to make a good product and deserve to make whatever information they feel is priviledged to be just that. Why would you fault their right to do so?

As far as cost, I bought these cams as a performance upgrade that I could do myself and save dealer shop expense. They were a little more than twice what I paid for a NARC which was essentially a metal box, so I feel I got a lot for my money. I believed the people, like Mike, who I trust to provide good information on these forums and I wasn't disappointed.

Cheers to you,
Rich
 

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I'm guessing these cam grinds are what they used to call in my day "trade secrets" or information the manufacturers like to keep close to their chest so every other machine shop can't start making them. I figure these guys spent the time, money and effort to do the R & D to make a good product and deserve to make whatever information they feel is priviledged to be just that. Why would you fault their right to do so?
I am fully respective of trade secrets and understand the rationale behind embracing them from a manufacturer's standpoint...though I must say that to postulate that 'every other machine shop' can reproduce cam grinds given some lift and duration specs is a really bad assumption.

I'm just saying that it is hard from me to simply take a leap of faith that secret cam grind A is better than the thunderbike grind (published specs), early 790 grind (published specs), etc. when my annual performance upgrade budget is about 500 bones! Yeah, I know...I'm not the demographic the cam folks are aiming at, but I digress...

Anyway, even in cases where folks like Mike in VA or thruxton ton-up achieve measurable increases, these are guys whose bikes are modified beyond basic bolt-ons & much of these gains may be attributed to the sum of all things modified. I'm pretty sure my machine would not realize similar % gains in power...so I've really got nothing definitive to go with.

By the way, prescription drugs are evaluated using 3rd party, clinical trials prior to their approval for use by the FDA...the drug manufacturers don't simply say 'trust me'!!

Sorry for the diatribe. More discussion than the subject warrants....

Regards,

--Rich
 

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Rich I held out buying them for a long time to.Then i got to a point I had to have better cams if I was going to make more hp.I read what johns bike did that got me thinking there might be something to the 813 cams. I ordered them and checked the specs on them to make sure I got what I wanted .I can tell you they are what they are the real deal.A better street cam then the 01 790 cam.More lift more duration.But not to the point where they should tear up parts or make your bike un streetable.Allso carlos is a man of his word .
Give him a call and talk to him you wont go wrong with his cam.
 

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Yeah, I think that Rich guy was just diatribing and trolling. If he really wanted to know about the parts he would have called the source.

(BTW, when I said "every other machine shop" it was hyperbole not a postulate. Also, in reference to medicines, of course the FDA knows how they work. My point was that consumers generally don't.)
 

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No that's not a fair statement rmak. beemerrich has been around for a while. I'm sure he's just trying to get as much info as he can prior to buying. I'm doing the same with carbs.

He may not yet be as familiar as we are with Carlos and the expertise at TPUSA.

But I think your point about trade secrets is totally fair and valid. I see no reason why a manufacturer of new cams should reveal the specifics of the regrind, as long as they stand by their claims on performance advantages, and we all know that Triumph Performance USA are a damn fine vendor, and do exactly that.
 

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I can tell you they are what they are the real deal.A better street cam then the 01 790 cam.More lift more duration.But not to the point where they should tear up parts or make your bike un streetable.Allso carlos is a man of his word .
Give him a call and talk to him you wont go wrong with his cam.
Thanks mike. Like I said, the fact that you and ton-up have had success fitting the cam is encouraging. Based on your testimony, I can live with the idea that its the best cam going.

However, as you might remember, I've got a spare head that I'm fitting on my bike that's had its deck shaved...while I'm glad to hear the cam has 'more lift', without knowing how much more lift it has, I can't know if I can run the cam without having hard parts meet at TDC.

I've called the vendor, spoke with the man himself, and got nowhere other than 'it has more lift & duration...try it, you'll like it'. Thanks for nothing.

Cheers,

--Rich
 

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Discussion Starter · #20 · (Edited)
Yeah, I think that Rich guy was just diatribing and trolling. If he really wanted to know about the parts he would have called the source.

(BTW, when I said "every other machine shop" it was hyperbole not a postulate. Also, in reference to medicines, of course the FDA knows how they work. My point was that consumers generally don't.)
not always true, my friend. we have medicines out their that we have absolutely no idea about their mechanism or how they do what they do!

but, getting back on topic, the 813 cams seem to be the overwhelming favorite here and from what i have read, everyone who has gone with them has been pleased. with other cams it seems hit or miss. when i get cams i will be going with the 813.
 
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