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Old 01-02-2013, 12:23 PM   #1085
troy safari carpente
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Joined: Nov 2005
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Originally Posted by rmhrc628 View Post
Can someone with more info please advise on the reason for alloy tanks over plastic on the Crf rallye ?

Haven't we used non plastic tanks 30 years ago and learnt they were no good? (steel)

I can't figure out why Honda persist with alloy tanks. Is the reason they are still r and deeing?
Originally Posted by doyle View Post
I've asked and received zero answers. With the might of HRC, I would suspect plastic tanks or a full plastic subframe could be developed pretty readily. It's not like it's new technology and they even exist for the CRF already. I was also thinking heat dissipation. Perhaps the aluminum is acting as a bit of a heat sink to help combat the extreme temperatures expected in Dakar? Either way, they've changed quite a bit even from Morocco to Peru, but they remain alloy no one seems to want to answer why that is.
Originally Posted by bajaboundmoto View Post
Only a guess but I'd say it's because everything is still being figured out. Why spend the mega $$ to make plastic until it's a set shape.
In some FBook pics you see the rear view of the X and both side tanks look to have a little box at the top tip. That was because not too long back they cut off the top few inces of tank and relocated those ounces down lower. So the side plate was left with a sharp point and they basically just filled it in. I only know because I asked "WTF?" when a couple weeks ago I saw the sharp point of the side tank. They said it was going to get filled in, but not with gas.
If that was plastic it would be huge $ to make that change.
Guestimate only.

And yes it might be HRC but there's always a budget. If there was no budget wouldn't they have supplied all their own support?
And even the little tool boxes in the bash plates are new and weren't installed until bikes were at Lima. They were made by JC's brother and in his shop a couple weeks ago.
Yes Factory HRC but...
I think it is a combination of two things (possibly) the R & D (ongoing development) vs expense - knocking out new dyes, and moulds to make repeated modifications; (Vers.1, Vers 1.2... Vers 2.0, Ver 3.2... etc. as per Bajabounds obsrevations/insider info. ) does not come cheap... because as tim pointed out also... even if it is "HRC" money is obviously not "no object".

The second theory (along doyles train of thought) comes to me after playting with some plastic multi tanked Husabergs in hot climates, with all the associated plumbing, breathers, fuel lines, different tank volumes AND FUEL INJECTION Not so much for heat dissapation... but the structural integrity of aluminium (and the fact that it does not breathe or expand as the plastic tanks tend to) may well be the HRC engineers idea towards solving the problem of fuel starvation/vapour lock/boiling fuel etc. when at high altitude/high temperatures that we have seen on some of the El dakar stages these last years?

As it has always been a cornerstone of HRC's plan for this new CRF Rally project to run EFI, and we know that the bubbling/fuel expansion/airlock/boiling fuel issues of the last couple editions that commonly plague the multi tanked/different volumetric capacity tanks, plastic kit bikes (the FI husa's spring to mind again) then maybe the Aruminirum tank is the Japanese engineers ace in the hole* as far as getting the FI to work up at 20,000 ft cruising altitude...?

Willing to forgo some of the advantages that plastic/nylon has over aluminium, for the sake of reliable engine management perhaps?

*Then again... wasn't the "official" explanation of helders DNF in Marocco a "vapour rock" though...? ummm... you get those in the tank... not the engine... don't you?
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