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Marque Remarks => Yamaha => Topic started by: YUMASTEPSIDE on September 16, 2010, 04:04:41 pm

Title: YZ400C Jetting- now IT400C discussion
Post by: YUMASTEPSIDE on September 16, 2010, 04:04:41 pm

Anyone know the standard jetting for a YZ400C ??

                    Roger

Title: Re: YZ400C Jetting
Post by: IT400C on September 16, 2010, 04:17:38 pm

Hi Roger - was told it was:

According to the service data sheet

38mm Mikuni

Main Jet / Pilot Jet - 370 / 60
Needle Jet / Jet Needle-Clip position - Q-0 / 6F16-3
Slide Cutaway  - 3.0
Float Level - 18mm
Mixture screw - 1 1/2 turns out

Title: Re: YZ400C Jetting
Post by: YUMASTEPSIDE on September 16, 2010, 10:56:16 pm

Thanks Tony, I got that IT article, thanks again.

                          Roger

Title: Re: YZ400C Jetting
Post by: IT400C on September 17, 2010, 10:37:28 am

I did get a slightly different jetting spec from another source - It's at home though - I'll dig it out and let you know what it was too.

Title: Re: YZ400C Jetting
Post by: YUMASTEPSIDE on September 18, 2010, 05:02:57 pm

.......I'm going to hijack my own thread here, but........after having a good look at Al Roof's " Chris Carter Replica", with no disrespect to Al, I don't think its much of a replica. Going on appearances only, it looks like he's only changed the rear guard, headlight, bars and muffler and turned the rear brke arm over.
   After reading the article you sent me last week, I must have read it when it originally came out, because the majority of the things done to the American bikes were the same as we did to our 400C's back in '77.
   
                    Roger

Title: Re: YZ400C Jetting
Post by: IT400C on September 18, 2010, 09:53:30 pm

Mine's going to be in the next Trailzone - still not finished but I have done most of the major changes as mentioned in the article (including the snail cam rear end).

In the process of sorting a centrestand - I have a genuine NOS Yamaha IT175D centrestand which is the correct height, and would work if I drilled the lower frame rails as they did in the article, but I'm not too keen to alter a good standard frame - I'll probably get one made to use the 2 x holes/plates at the back of the frame (I believe they were where the frame was mounted on the assembly line in Japan) - I know they used to work for centrestands on the D-E-F..

Apart from that, I just have a few very minor details to sort out to complete the replica.

(I'll PM or email you about the other thing you mentioned, but yes, I agree)

Title: Re: YZ400C Jetting
Post by: IT400C on September 18, 2010, 10:44:53 pm

just pm'd you

Title: Re: YZ400C Jetting
Post by: IT400C on September 18, 2010, 10:45:43 pm

Hey Roger - what are you doing about a centrestand?

Title: Re: YZ400C Jetting
Post by: YUMASTEPSIDE on September 19, 2010, 07:56:15 am

If I cant find one thats close I'll make one from scratch.

                  Roger

Title: Re: YZ400C Jetting- now IT400C discussion
Post by: steveo247 on September 21, 2010, 09:09:38 pm

hey guys dont know it this helps you or not, but on the vmx swapmeet site there is

"1977-78-79 it 175 n.o.s. center stand. a very rare piece. genuine yamaha. never mounted complete kit. $150.00 & shipping. Thanks , Steve"

"Steve Kittleson
Ventura, CA
Phone: (805) 340-1952"

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