Car vs MC Colortune

Been a while since I've posted anything......Anyway, I just ordered a colortune, but unfortunately I ordered the wrong one. I know there's been several discussions on colortunes and even found a little information on the difference between the auto and motorcycle versions. I ended up with the Gunson G4074 (should have been the G4170). So, my question is whether or not I need to exchange it for the correct model for either accuracy or safety? It sounds like the volume is larger (and therefore compression lower) on the auto version. Is that significant enough to exchange it. Not a huge deal to exchange, but it will cost $ for shipping, and time to send it back. Any advice would be appreciated. Thanks!

 

I wouldn't think there would be any difference in the result given by the plug. Without looking at both types, I would suspect the only difference may be the leads supplied in the kit. Eg the car lead may not fit as it may be set up for the screw on "knob" on the plug. This may mean it wont fit into your plug caps.


All guesswork though.

Cheers
HG

 

I would exchange it for the correct motorcycle one.
You will have this Colortune for many years, and will always have in the back of your mind that it may not be as accurate as it could be, despite what people will may you.
The mail cost is nothing spread over a long period - get the right one and be happy.

 

Gunsons have a manual available that explains the difference. there are minor differences but whether the difference matters to you is taotally your choice.


Damn good read though, much better the the little piece of paper that comes in the kit.

Especially section 4b. 8)

 

Looks like I should dig into the manual at Gunsons. The place I ordered from just responded that the difference is only in the marketing. From what I gather from your perspective (in this and previous strings) it's more than just the marketing. I guess I will do some reading, and maybe others have experience using both models? Anyway, thanks for the input......more to come. Cheers!

 

I would only be concerned about the reach and thread of the unit. If they are correct, you should be ok and the information is universal in application. So don't sweat the p/n difference.

 

I have used both at carb clinics. I own a colortune 500 auto version. It will tune a carb quite well. I do prefer the motorcycle version mainly due to the insulator around the center electrode. My auto version needed to be taped and heat shrinked before I could keep it from arcing across to the base.

 

I have two of the colortune 500 auto versions so I can adjust both carbs on the same side at once and they work fine. They wouldn't work without the insulators but I called Gunson and they mailed them to me for free.

 

I found out that Gunson's recently (about 12 months ago) modified the car version so that it will work for motorcycles as well. It wasn't clear whether the new car version is identical to the motorcylce version and they are phasing the motorcycle one out, or whether it's just a case of "it should be fine."

When you talk about the car version needing additional insulation, what end of the part do you mean (for lack of spark plug terminology knowledge......the spark end or the wire connection end?) I ssume the wire connection end, but I tried to find pictures of older versions online to see if I could tell the difference, but I didn't find many pictures (and none helped). What should I be looking for? Thanks!

 

The wire connection end. More specifically where the sparkplug wire attaches. I could heat shrink the other "spark" end . but I don't think heat shrink would stand up too well inside the combustion chamber. :wink:

 

That seemed obvious to me......but I've also been wrong about "obvious" things (I'm sure my wife would be happy to provide examples!). Sounds like mine should work fine then. The ceramic is about 1/8" above the collar, and then there's a plastic extension insulator on the shaft that's another 1/4" with just enough thread to screw the adapter on.

Thanks for the input!

 

I believe the area they are referring to needing insulation is where you little ceramic collar is.
I have the m/c version and it has the ceramic collar too.