Different kinds of Rollmaster TC's - Pics inside

[Blazer406]

Well......I went to put my engine together.... after fixing a spun #2 cam bearing...... my 60 miles (only mileage on it) Rollmaster timing set (.002" oversize to compensate for line boring crank) was too loose.... had about 3/8" slop...... I called or looked at the normal suppliers for an .005 setup. I ran across an authorized vendor that had a .004 oversize in stock... and they could get it here fairly quick.... so I bought it.....knowing it wasn't exactly what I was hunting.... but it was alot closer than what I had. Meanwhile... I had emailed Romac (maker of Rollmaster) and quizzed them about if there was supposed to be any markings on the sprockets....... to positively ID what size (std.... .002 oversize....... .004 oversize.... .005 oversize...... .010 oversize) I had..... they said there should be markings on the crank gear. Upon close inspection... I only see the two dots on the crank gear..... nothing else. The cam gear has "rollmaster" inscribed into the hub area. Disappointed... I cannot positively ID mine as .002" oversize other than my original order that says I ordered that size. I also had one supplier tell me they no longer offer the 9 keyway crank gears...they are all 7 keyway crank gears now....

Fast forward til today.... my new CS7010-4 came in.... supposedly .004 oversize I suppose.... Upon opening the box.... which said "Rollmaster" Red Series....... I noticed four differences worthy of not....as compared to my 0.002" set.

1. The teeth of the crank gear were flame hardened. My original one was not.
2. The crank gear had many markings on it for the different degrees. My other one didn't.
3. There was a "5" inscribed on the crank gear.... which backs up what Romac told me in an email.... this is really a 0.005" oversize set....the size I really wanted anyway.
4. The crank gear only has 7 keyways... the other one I have has 9 keyways.

I also noticed a difference in the color of the chain.... looks to be a different brand of chain. Looking at the cam sprocket....It had "rollmaster" stamped in the very outer portion of the sprocket just below the teeth..... completely different location from the other one.

Upon measuring both sets.... It is obvious the cam sprockets appear to be identical.....the crank sprockets are where the difference is that "takes-up" the slack incurred due to a line boring......

Here is the measurements I got to the best of my measuring ability with Starrett 9" Dial Calipers...

Both cam sprockets measured 4.518" diameter between the root of opposing teeth (180° apart)..... and 4.910" tooth tip to tooth tip... between opposing teeth (180° apart).

The .002 set had a crank sprocket that was 2.150" diameter between opposing tooth roots. It had a diameter of 2.50" from tooth tip to tooth tip.... between opposing teeth.

The .004 set had a crank sprocket that was 2.157" diameter between opposing tooth roots. It had a diameter of 2.50" from tooth tip to tooth tip.... between opposing teeth.

In conclusion... the .004 set would in effect raise the roller up .0035 (3-1/2 thousandths) over the .002 set.

I could be off slightly.... but this is fairly close..... in case anyone might can find some use from all this useless information.....

What does your rollmaster look like?

 

[charlief1]

Good info Blazer. I will point out that rollmaster was bought out in the last year or so that may be the diff in manufacturing.

 

[Just a Six??]

I have a Rollmaster 9 keyway I got from Mike at FT 2 years ago. NO Markings or Stamping on Either sprocket. Says 1014 on the package & thats it. Seems that a part should be Stamped with a size on it but Nothing on mine at all?? Supposed to be 4 thous from stock but how do I know 100% with no markings on it??
Seems pretty Sloppy to me. Maybe they just use whats "handy" to throw in the package as long as its close to what you want? I just don't get why when you punch out parts you Don't Stamp Them?? Every other part has a number on it thats worth any amount of value & especially something this Important! Maybe thats why some say they have Noisy Chains? Seems like BS to me they cant put a stamp so you know 100% what is being installed?

 

[rw87tt]

The numbers on the crank gear on mine were eched with an engraver. These Rollmaster sets are not cheap at nearly 150 dollars. I think they are over priced considering the quality.