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Thermobob

7K views 30 replies 11 participants last post by  Green Bastard 
#1 ·
So What are the differences in thermo’s being sold? Watt man v Procycle
 
#2 · (Edited)
So What are the differences in thermo’s being sold? Watt man v Procycle
Good question!

Maybe, functionally, there are NO differences between radiator bypasses available.

Then . . . if considering a Thermo-Bob-like device, what are your own expectations? What consequences, pro and con, if any, do you expect from such a device?

I'll bet, at the operational level, either will stabilize coolant temperature more fully, and at a higher degree, than the OEM system. The actual "Thermo-Bob," as far as I know, has been designed and manufactured in the USA with transparency suggesting competent design and production, with extensive testing. Don't know much about the Procycle, other than the vendor seems an ethical business (from Internet reports). "Copy cat?" Generally, a device, "obvious to a journeyman craftsman skilled in the trade," (lots of radiator bypasses exist, over a wide range of liquid-cooled engines) cannot be protected by a patent [layman's (non-lawyers's) opinion].

Regardless, your own expectations and requirements remain key, IMHO.
 
#3 ·
What is the thermostat temperature of the ProCycle radiator by-pass system?

The Thermo-Bob thermostat temperature is 195F, which is a Whole Lot better than the oem 160F for both engine cylinder & engine oil.
 
#10 ·
No adding a thermobob won't correct a pre-existing bore problem. Again, here's a related post on the subject;Honestly I think the bore has a propensity to go out of round on the bottom end regardless......but the T bob may lessen the distortion to the extent that the rings can compensate. Cary theorized that after a number of heat cycles the bore tends to become relatively static - which is why it stays fairly stable after a 685 rebore job. The '08's and '09's have a well deserved reputation for oil burning due to the ring (re)design, not because the bores are way worse than earlier or later bikes.....this is based on my review of some of KLRCary's material as well as my discussions with Eaglemike. Cary described the bore distortion as a design issue. Mike's belief is that if you put an earlier or later piston/ring set into a virgin 2008 or 2009 bore that it would have no greater chance of being an oil burner than other years.

To recap my thoughts;

- early Gen2's ring design was poor leading to a much higher incidence of oil consumption; as the bores distorted the rings couldn't control the oil.
- KLR650's have a propensity for some degree of bore distortion due to the design (lack of support on the bottom end of the sleeve and the thickness of the sleeve)
- the bore shape tends to stay relatively static after a certain number of heat cycles which is why the 685 kits usually solve oil consumption issues (and Mike's rings seal better)
- Aftermarket sleeves such as the 705 sleeve are beefier and don't distort much, if at all.
- the Thermobob helps lessen bore distortion by greatly reducing the delta T of entering and leaving water (cold shocking the cylinder). It's logical, given Cary's thoughts on the heat cycle issue, that the benefit of the thermobob is much greater if it's installed when new or very early in the engine's life. That said, it can only help regardless of when it's installed (do no harm! :) )

....at least that's the synopsis I've come up with after some research and discussions with the guys that have the first hand knowledge and experience on the subject.


Dave
 
#11 ·
As far as the OP's question;

- the only differences APPEAR to be that the Procycle kit gives you hoses and a rad cap for the additional $80.00. Bills part looks a little different, the bypass T looks like a nicer part and h gives you a spare T stat. I personally wouldn't want the hoses and the stock hoses are holding up well on my 2000 and 2001 but to each thier own. The Thermobob is proven to be a high quality kit, the Procycle one may or may not be.

regardless of all the above, I question the "in house designed" claim by Procycle and would buy the Thermobob out of general principle 'cause I don't like people ripping off other peoples designs.

2 cents,
Dave
 
#13 ·
Good points, Dave!

The THEORY (a Thermo-Bob reduces/inhibits/minimizes cylinder bore distortion) appears plausible; may be entirely valid. Yet, as you mention . . . corroborative data supporting the theory remains elusive. Anecdotes ("point estimates") may exist; the phenomenon may be universal. Availability of a statistically significant sample seems unlikely, to me.

That said, "Stands to reason," on the premise of positive Thermo-Bob implication regarding cylinder bore integrity, may be positive incentive (along with other factors) for Thermo-Bob installation .
 
#15 ·
We have drifter away a bit from the original post, but I will point out that when my first 2008 started burning oil at a quart per thousand miles, I viewed it as self changing the oil. All I had to do was add oil as needed and change the filter every few thousand miles.
 
#22 ·
Are the ProCycle brand of radiator by-pass kits still being sold with the 180F thermostat?

Or have they up-graded to the 195F thermostat that is Finally being produced in China in the proper oem KLR size.

Living in a higher altitude, cooler climate the 195F thermostat would be most beneficial.
 
#23 ·
According to their website it’s still a 180. In my experience this is still too low. Although I didn’t scientifically measure, I don’t perceive any difference in warmup time or operating temp since installation...same old wild swing. I’m glad to hear there is now a 195 stocker available.
 
#24 ·
I'll suggest that you should use the 195F Watt-man Thermo-Bob 2 thermostat in the ProCycle radiator By-pass assembly if possible.
Better yet, purchase the Watt-man Thermo-Bob 2 in the first place. :)
 
#27 ·
Yes, it will. It is the stock KLR thermostat and the thermostats that watt-man uses are identically sized to the OEM.
 
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