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General Category => Maintenance => Topic started by: iridewheelies on October 26, 2019, 03:15:50 PM

Title: Cam timing
Post by: iridewheelies on October 26, 2019, 03:15:50 PM
Heres some pics of the cam timing intake first. Bike on side stand. Seems a half tooth off or something they definitely arent even. Cracking her open to do some work this winter I want to port it, big valves but I'd have to find a good cam seats springs. Anyone ported their head?

Need to get the front end r1 swapped. I had a 2000 r1 I bought for dirt cheap I should have parted it out. It ripped.

The bike ran pretty damn good but it was getting symptoms of tight valves. The lobes look alright.
This bike is an 85 1100 I assume, it has a lot of compression hand cranking it. I can move the chain pretty well with the cover off but there is no rubbing on the guide 
Title: Re: Cam timing
Post by: iridewheelies on October 26, 2019, 03:38:07 PM
Nullify those pictures. These are better lol. Still doesn't seem right. Intake first. Stretched chain?
Title: Re: Cam timing
Post by: CutterBill on October 26, 2019, 07:14:40 PM
Just buy the Yamaha Service Manual. It will show you exactly how to time the cams without guesswork. About $90 from Yamaha online.
Bill
Title: Re: Cam timing
Post by: iridewheelies on October 27, 2019, 02:08:45 AM
Thanks your comment had a lot of valuable information. I wont be disassembling for a while but soon enough I'll get my hands on a good manual. A manual only tells you so much. Maybe I should pull the tensioner sometime and see how far out it is. Is there a reliable pin count method? I seen a post about a few holes in the cam caps and some dimples that would show thru the holes. I was going to adjust the valves but the timing could be off the chain may be stretched, so I may be in for a top end refresh. Any advice is greatly appreciated like I said the bike ran pretty decent it made good power and the compression is pretty great turning by hand. U can hear the air compressing
Title: Re: Cam timing
Post by: FJ_Hooligan on October 27, 2019, 01:34:40 PM
How far off are the dots in the holes of the #3 cam caps?
Title: Re: Cam timing
Post by: racerrad8 on October 27, 2019, 06:29:41 PM
You are a tooth off on the crank (1/2 tooth on the cams). It is a challenging thing to install the cams properly.

Yes, there will be some chain stretch, but that can be adjusted out using the adjustable Slotted Camshaft Gears (http://www.rpmracingca.com/proddetail.asp?prod=Head%3ASCG).

BTW, what are you referring to with "cam seat springs"?

Randy - RPM
Title: Re: Cam timing
Post by: iridewheelies on October 27, 2019, 07:44:10 PM
I am referring to performance cams, big valves, upgraded springs for more lift ect. I'd either have to cut the seats or get new ones installed..
I wanted to make the bike pick up some power this winter. For clarification, I have never taken the cams out, I haven't done anything this is what it looked like when I took the valve cover off lol
Title: Re: Cam timing
Post by: racerrad8 on October 27, 2019, 08:50:55 PM
Understood.

The valve seats can be easily opened up for the oversize valves.

Let us know,  we are a Web Cam dealer and we have all of the other parts; oversize valves,  proper springs,  better valve stems seals and on & on.

Someone has had the cams out,  they were most likely not delivered by Yamaha in the condition.

Randy - RPM
Title: Re: Cam timing
Post by: iridewheelies on October 28, 2019, 08:24:25 AM
I dont think it's been opened up for many years. The guide bolts on top were insanely tight and made the distinct sound of braking loose. I drilled 2 of the ignition stator cover bolts they were insanely tight lol it's got 12k miles on clock but it has the squealer mod so i have the speedo cable out. I use my phone for a speedo haha I need to bring a compression tester home from the shop and test.
Title: Re: Cam timing
Post by: FJ_Hooligan on October 29, 2019, 09:16:47 AM
Exhaust cam looks slightly advanced but not too bad. 

As Randy said, that can be adjusted with slotted cam sprockets.

What are the symptoms of tight valves you mention in your first post?  Have you measured the clearances yet?
Title: Re: Cam timing
Post by: racerrad8 on October 29, 2019, 09:37:02 PM
And with the cams in that position,  the timing mark on the crank rotor?

Randy  - RPM
Title: Re: Cam timing
Post by: iridewheelies on November 03, 2019, 01:04:55 AM
For the symptoms the bike began hard starting when warm/hot. For example at the gas station, it would crank and crank. Turn the key off and back on try again itll start. The last time I put gas in it, it made a pretty bad backfire out of the exhaust like a gun shot. Battery is weak I know that. Sometimes it'll crank and wont get spark but that's only after sitting a few weeks. I'm betting that the valves are pretty tight. I don't have a set of feeler gauges at home. My bro has them. I'll check the mark on the rotor
Title: Re: Cam timing
Post by: iridewheelies on November 10, 2019, 02:14:47 AM
Been busy working. Hell. It was 65 outside today, would have been a great day to cruise. Anyways, I'm not rushing into this build, because I still dont know what I want to do with the bike. Here is the ignition coil rotor, double checked made sure the cams were in same position. Is it just me or does this ignition look new lol
Title: Re: Cam timing
Post by: racerrad8 on November 10, 2019, 10:11:31 AM
You need to rotate the crank around twice and align the "T" mark with the line on the front pick up coil.

That establishes TDC and then you can determine the Cam timing.

Randy - RPM
Title: Re: Cam timing
Post by: iridewheelies on November 11, 2019, 06:36:51 PM
What's the best brand repair manual to get? Any pdfs out there? In the meantime I will probably determine tdc through the plug holes... again I'm in no real hurry the bikes put away for the winter. Just want to familiarize myself with the engine, and decide the best course of action... thanks for all of the directions. A compression test will give me the best idea on whether I'm going to tear down and refresh. Odds are I may be down on a hole or two. Give me some time and I'll come back with some solid numbers, from valve clearance to comp. And timing, with #1 on tdc. Thanks guys.
Title: Re: Cam timing
Post by: Tuned forks on November 11, 2019, 07:34:00 PM
Probably not what you wanted for an answer but the best is the FYSM.

https://www.yamahapubs.com/results.php?cat-id=3&year=1993&family=FJ1200&lang=en (https://www.yamahapubs.com/results.php?cat-id=3&year=1993&family=FJ1200&lang=en)

Joe