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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.
 

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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.
 

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The Thermo-Bob thermostat temperature is 195F, which is a Whole Lot better than the oem 160F for both engine cylinder & engine oil.
Just askin': At what age and mileage did you install a Thermo-Bob on your 1987 KLR650?

("Inquiring minds want to know!") :)
 

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Discussion Starter #6
It appears as though the only difference in Procycle version is upgraded silicone hoses. Everything else is the same
 

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Somewhere between 60,000 & 63,000 miles around about 2011-2012, IIRC.
Thanks for sharing! Glad your engine endured those miles before the modification.

Back during the excessive-oil-consumption disaster of 2008-09 models, some opined the lack of a Thermo-Bob was responsible for this oil-guzzling phenomenon. Others insisted (and, probably still insist) the lack of a Thermo-Bob results in distorted (i.e., "ovalized") cylinder bore cross-sectioning. Don't know if those of this persuasion consider installation of a radiator bypass corrects this bore anomaly or not.

Regardless, the Thermo-Bob appears responsibly marketed, performing as advertised (stabilizing coolant temperature more fully and at a higher nominal operating temperature than the OEM cooling system), AFAIK. The 100,000-mile 2008 model of my riding partner proudly sports a Thermo-Bob! :)
 

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Thanks for sharing! Glad your engine endured those miles before the modification.

Back during the excessive-oil-consumption disaster of 2008-09 models, some opined the lack of a Thermo-Bob was responsible for this oil-guzzling phenomenon. Others insisted (and, probably still insist) the lack of a Thermo-Bob results in distorted (i.e., "ovalized") cylinder bore cross-sectioning. Don't know if those of this persuasion consider installation of a radiator bypass corrects this bore anomaly or not.

Regardless, the Thermo-Bob appears responsibly marketed, performing as advertised (stabilizing coolant temperature more fully and at a higher nominal operating temperature than the OEM cooling system), AFAIK. The 100,000-mile 2008 model of my riding partner proudly sports a Thermo-Bob! :)
Damocles, Yours is the First I've heard of anyone suggesting the addition of a Thermo-Bob would correct the so-called "ovalized" bore. Did you just make that up? Interesting thought non the less.
 

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Damocles, Yours is the First I've heard of anyone suggesting the addition of a Thermo-Bob would correct the so-called "ovalized" bore. Did you just make that up? Interesting thought non the less.
In my post, I intended disclosing my own ignorance of whether the concept was harbored by anyone or not:

"Don't know if those of this persuasion [lack of a radiator bypass distorts a cylinder bore] consider installation of a radiator bypass corrects this bore anomaly or not." (Bracketed phrase added to quotation for clarification.)

Again, I apologize for my, "Failure to communicate!"

Does the lack of a Thermo-Bob distort engine cylinder bores? On ALL KLR650s running without radiator bypasses? If so, in the service life of KLR650s, early installation of Thermo-Bobs appear critical, if the ovalization is not corrected by the device.

If a radiator bypass only PREVENTS cylinder bore distortion, I'd wonder whether any non-Thermo-Bobbed engine has a symmetrical cylinder bore; if the bore geometry remains true without a bypass, I'd wonder why. Don't know if the vendor claims avoidance of cylinder bore distortion from use of the product, or offers any test data to that effect.

Just for the record, I think evidence suggests incorrect piston/ring design and/or construction was responsible for the excessive oil consumption of the circa 2008 model KLR650s, not the absence of Thermo-Bobs. What evidence? Fewer instances of excessive oil consumption reported after re-design of pistons and rings by Kawasaki, say, on circa 2009 and later models. My opinion only; YMMV!

Then again, some thought the absence of a PCV Valve Mod was the cause of excessive oil consumption! :)
 

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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
 

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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
 

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Does the lack of a Thermo-Bob distort engine cylinder bores? On ALL KLR650s running without radiator bypasses? If so, in the service life of KLR650s, early installation of Thermo-Bobs appear critical, if the ovalization is not corrected by the device.

If a radiator bypass only PREVENTS cylinder bore distortion, I'd wonder whether any non-Thermo-Bobbed engine has a symmetrical cylinder bore; if the bore geometry remains true without a bypass, I'd wonder why. Don't know if the vendor claims avoidance of cylinder bore distortion from use of the product, or offers any test data to that effect.

Just for the record, I think evidence suggests incorrect piston/ring design and/or construction was responsible for the excessive oil consumption of the circa 2008 model KLR650s, not the absence of Thermo-Bobs. What evidence? Fewer instances of excessive oil consumption reported after re-design of pistons and rings by Kawasaki, say, on circa 2009 and later models. My opinion only; YMMV!

:)

1) it isn't the lack of a Thermbob that causes bore distortion, rather installing one may lessen it

2) nothing except a boring machine will correct an oval bore

3) No the vendor doesn't claim anything, nor will you find any evidence to support or dispel the concept; as discussed many times, this does not and will not exist. The physics either makes sense to you or it doesn't.

4) yes the ring redesign lessens oil consumption, see my previous post for thoughts on why.


People take potshots on the Thermobob all the time; frankly I couldn't care less if people want to use one or not. After carefully reviewing all the data available and talking to several people I consider subject matter experts, I was convinced (and still am) that it is a good addition to the KLR which can only have a positive effect. I don't think that every KLR without one will become an excessive oil burner, nor to I think adding one guarantees that your bike won't develop an oil burning issue......I DO think it is LESS LIKELY with the T bob and there is no way to measure or quantify this belief. Gen2's benefit more than Gen1's due to the larger rad and early Gen2's benefit more than later Gen2's due to the poor ring design's tentative ability to properly seal the bore, particularly if it is distorted to some degree. These are MY thoughts only


Dave
 

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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 .
 

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I have a Thermo-Bob, installed when bike was fairly new. I've never noticed a difference in where the temperature arrow resides after warmup and while riding, after installation compared to before. Should I have?
 

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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.
 

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The T-bob and the ProCycle units are significantly different as the T-bob thermostat hangs in an enclosure on the hose but the ProCycle mounts in an extended housing where the stocker goes. ProCycle includes a 180 deg thermostat.
 

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After further review...I see that the T-bob 2 is similar to the ProCycle version I purchase in March 2015. If the T-2 would have been available back then I would have purchased it instead.
 

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After further review...I see that the T-bob 2 is similar to the ProCycle version I purchase in March 2015. If the T-2 would have been available back then I would have purchased it instead.
Just curious, dallas (I basically favor a, "free market"), what factor(s) influenced your preference for T-2 over ProCycle?
 

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The T2 wasn’t available yet and I liked the mounting arrangement of the ProCycle version better. T1 was a blob hanging in the rad hose
 

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The T2 wasn’t available yet and I liked the mounting arrangement of the ProCycle version better. T1 was a blob hanging in the rad hose. Since I first read about the Thermobob here on this forum I would have preferred to follow your lead.
 
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