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After trying to figure out how to get a cam from TecBike for the last couple months it seems like that's not going to happen so I was wondering if anyone knows a US vendor of a performance cam or has a cam profile they would be willing to share that I could have one ground to spec?
 

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Let me ask a question. And I mean absolutely no disrespect here. After all, I have personally concocted some of the most hair-brained, fire-breathing and non-streetable motorcycle modifications in hillbilly history.

If you want hot cams in a Bobber, wouldn't it be wise to consider just buying the factory Thruxton-R cams? I mean, what reputable company is going to invest any real R&D time in developing cams for a bike they'll be lucky to ever sell 40 sets of cams for? Where's the profit in that? Do you really think Tec or some other small-potatoes company is going to do anything more than add a little lift and duration based on an educated guess and ship it? Are these amateur-designed cams going to function well in the long run with your factory valve springs and rockers? Who's going to do the testing to determine that? YOU are, that's who. And for what? I mean, how much more horsepower than a Thruxton-R are you really going to be able to squeeze out of your Bobber motor without adversely affecting durability and/or how smooth the power curve is? How much low end torque are you going to lose? And if the surface finish on the bearing journals isn't smooth enough, or the cams aren't properly toleranced or heat-treated and they ruin your head in a year or two, do you think Billy-Bob Inc. is going to buy you a new head?

Learn from my foolishness and misguided horsepower lust. I was the guinea pig on a professionally installed Wiseco forged big-bore kit that barely lasted thru break-in and they quit making rings for it a year later anyway, so I had to throw my cylinder bank in the scrap barrel and start over. I once bought eight Moriwaki valves for my Kawasaki that cost more than 16 Manley valves for a 427 Chevy Rat motor. I paid Jerry Branch, arguably the best motorcycle head man who ever lived (and formerly Elvis Presley's personal bike mechanic), to install them, and port and flow the head. When Jerry got them he called me and asked, "Who the h*ll designed these valves, some retard?" There was literally no way to fit them into the head for which they were supposedly designed without physical interference (both with each other, and with the pistons!). I returned the valves to Moriwaki and they refused to refund my money or make valves that fit. Old man Moriwaki said Jerry was not qualified to evaluate their valve design. ("He nah kwawifi to say").

PS: Trirocket-3, I absolutely LOVE your crazy sh!t so please totally disregard this and keep posting about your experiments. If your Bobber motor explodes between your knees, start a GoFundMe and I will chip-in.

-GPz/Gary
 

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Discussion Starter #4
All fair points. Is there anything else that needs to be done to swap a TTR cam in to the bobber? Any idea How much would that increase power all else being equal? Sure seems like the easy way to some more power. Not all that much fun, but easier and more reliable for sure.

As to why I want to do it the hard way? Well I suppose that’s because I’m still young enough and stubborn enough to want to do my own foolish things. That and Ive been taking a break from drinking the last couple months and don’t have anything else to do with my money to keep me entertained.
 

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TTR cam is the same as Bobber
My latest cam is going into my Speed Twin today, but will not dyno it straight away as am waiting for new PCV to arrive.
Trirocket3: TTR cams are identical to the Bobber's? Then what explains the dramatically different maximum horsepower and power/torque curves? Even porting, polishing and flowing the TTR head can not account the different performance characteristics. Surely the 11:1 vs 10:1 compression ratio factors in, but there has to be something more dramatic going on than just better flowing heads and higher compression to explain the dramatically different engine personalities. I hope I'm wrong. Because if I am, then I'm going to do some head work and claim my extra 20 HP!

-GPz/Gary
 

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Trirocket3 is right about the cams being the same on the Bobber and TTR. I just looked it up and both use ass'y number T1147025.

Sorry for my erroneous assumption but it is pretty exciting news to those of us who might want to turn our Bobber motors into TTR motors with factory reliability and durability.

Please share info on whatever else might be necessary to make this conversion.

-GPz/Gary
 

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Come on, I want my extra 20 ponies!! -GPz/Gary
The main difference is as you said compression, head off, flow/skim + cam = probably 5 rwhp more than the TTR, stock bobber air filters restrict after that.
Over the next couple of weeks I will be looking into combustion chamber dimensions & volumes of both heads to try & establish how much can be removed from the bobber head
to bring it up to similar spec to the TTR hopefully without the unfortunate side effect of piston/valve contact, which could be a trifle inconvenient.
 

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OK but, as mentioned, I'm skeptical that the realities of business (extremely low potential for meaningful sales) makes improbable that any company I would trust is going to invest in the R&D to make a quality cam that will not significantly adversely affect the durability, reliability, and streetability of my bike. Given that, what exactly would I have to do to turn my Bobber engine into a Thruxton-R engine?

It can't possibly be as simply as buying a Thruxton-R head, right? There's no way that's going to produce the 20HP difference that Triumph claims between the two machines.

How about buying a Thruxton-R head plus having my dealer install the Thruxton-R MAP? I doubt that's going to do it either.

So what else, exactly, differentiates the TTR engine from the Bobber engine? I stress "engine" because I already run K&N pods and very free-flowing exhaust, so let's exclude that from the performance difference equation. Are the throttle bodies the same? Pistons? I can make time to look those up myself but somebody has to have already gone thru this exercise of figuring out exactly what differentiates the TTR motor from the Bobber motor to account for the supposed 20HP difference. Could it really be just the head, the airbox, the exhaust and the MAP? I seriously doubt it.

-GPz/Gary
 

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It is the head, air supply, lighter stator, map & rpm increase
Throttle bodies/ pistons ect same.
My bobber was at 111hp with TTR head, some flowing, one of my cams, exhaust & pcv.
A few quid & a little effort, cheap (relatively) easy power.
Not many bikes will yield such a power hike for so little expense.
 

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Very interesting topic and I’m enjoying following this thread.
Unfortunately it’s one modification I won’t be making as changing the cams messes with the very strict EURO emissions laws.
I can easily change the slip-on exhausts and Xpipe, but changing the cams/head every year will become annoying all too quickly...:(
 

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That reminds me — I farted once in Europe but it was almost 7 years ago. Has the statute of limitations run out or can I still be sent to prison?

-GPz/Gary
 

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That reminds me — I farted once in Europe but it was almost 7 years ago. Has the statute of limitations run out or can I still be sent to prison?

-GPz/Gary
Unfortunately any event that happened before October 2015 is still subject to a 15 year statute of limitations, so I’m afraid your fart excludes you from entering the Kingdom of Spain :nerd:>:)
 

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Well that’s unfortunate but I certainly appreciate the heads up.

I remain deeply concerned about my favorite member Trirocket3 over in the UK though. I know you don’t have the death penalty in Europe anymore but whatever the maximum criminal penalty is I’m sure he’s going to get it when they find out all the sh!t he’s done to his motorcycles. HelI, I think he changed his own oil once and spilled several drops onto his lawn. That conviction alone will put the poor glorious [email protected] behind bars for life.

FREE TRIROCKET THREE!!!
 

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Well that’s unfortunate but I certainly appreciate the heads up.

I remain deeply concerned about my favorite member Trirocket3 over in the UK though. I know you don’t have the death penalty in Europe anymore but whatever the maximum criminal penalty is I’m sure he’s going to get it when they find out all the sh!t he’s done to his motorcycles. HelI, I think he changed his own oil once and spilled several drops onto his lawn. That conviction alone will put the poor glorious [email protected] behind bars for life.

FREE TRIROCKET THREE!!!
Thanks Stinky Gary :)
 
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