Tachometer Readings Post your tachometer readings for your motor in here or ask others what they are getting out of their motor/prop combos!

Magnum XLS 91A BB

Old 11-06-2002, 11:38 PM
Senior Member
Thread Starter
Join Date: Apr 2002
Location: Sarasota, FL
Posts: 1,502
Likes: 0
Received 0 Likes on 0 Posts
Default Magnum XLS 91A BB

Magnum XLS 91A BB 14x6 MAS "K" 10.5K Stock muffler 3%N, 18% (50/50)
This was richened up, I did not tach it at peak. The engine had 5, 5 min RICH runs, with 10 min cool down in between, for break-in. Break-in was with 5%N, 22%O(60% Castor/40% Coopers Blend Synthetic).
Bore (mm) 27.5
Stroke (mm) 26.0
Practical r.p.m. 2,000-12,000
Power (b.h.p.) 2.8
Weight (gram/ounce) 672g/ 23.7oz
Normal Propeller 13x6, 14x5

It's the size and weight if a light .61, but gobs more power. Excellent transition, idles with the 14x6 at 2200 RPM (it vibrates a lot though), 2600 RPM is better. Only I thing, right out of the box, the idle needle was way too lean, which made starting and break-in difficultly. I adjusted it 2 turns out from closed, and now after it's primed, it'll start first flip. Hot restarts were no problem. This engine is very tight, I lubed it up at first with after run oil.

I have 3 Mag's and all three have performed just like the same displacement FX engines.

The link:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.